JP4191064B2 - Steam cooker - Google Patents

Description

  The present invention relates to a steam cooker.

  2. Description of the Related Art Conventionally, as a steam cooker that performs cooking of an object to be heated such as food using steam, there is one that sends superheated steam into an oven cabinet (see, for example, Patent Document 1 (Japanese Patent Laid-Open No. Hei 8-49854)). . This steam cooker includes a steam generator that generates steam by providing a heater along a vertical plane in the pot, and a steam superheater that generates superheated steam by heating the steam generated by the steam generator. The superheated steam generated by the steam superheater is fed into the oven to cook food.

  By the way, in the said steam cooker, when the door of the said oven warehouse is opened at the time of completion | finish of cooking, there exists a danger that a user may get burned by the superheated steam in an oven warehouse blowing out of a warehouse. Therefore, in the steam convection oven described in Patent Document 2 (Japanese Patent Application Laid-Open No. 9-89260), the exhaust fan is operated before the oven door is opened to discharge the steam and hot air in the oven chamber to the outside. I have to.

However, the steam convection oven described in Patent Document 2 has the following problems. That is, as described above, in order to start the operation of the exhaust fan after detecting the user's intention to open the door, it is constant from the start of energization to the motor of the exhaust fan until the rotational speed of steady operation is reached. The time lag is inevitable. For this reason, there is a case where the oven door is opened in a state where high-temperature superheated steam remains in the oven chamber, which is dangerous for the user.
JP-A-8-49854 (FIG. 8) JP-A-9-89260

  Therefore, an object of the present invention is to provide a steam cooker that can quickly exhaust the superheated steam in the heating chamber to the outside, and is safe even if the user opens the door of the heating chamber.

In order to solve the above problems, the steam cooker of the present invention is:
A steam generator for generating steam;
A heating chamber for heating an object to be heated by steam supplied from the steam generator;
An exhaust passage for discharging steam in the heating chamber to the outside;
A damper for opening and closing the exhaust passage;
An exhaust duct that guides the steam discharged through the exhaust passage along with the opening of the damper to the exhaust port;
The heating chamber and the exhaust duct are connected to each other, and a discharge passage is provided that guides the surplus steam in the heating chamber to the exhaust duct .

According to the above configuration, the opening operation of the holder damper to open and close the exhaust passage for discharging the vapor of the heating chamber to the outside, for example, by a controller or the like, the user tries to open the door of the heating chamber be performed by detecting the will, the user can discharge the steam quickly and reliably the heating chamber when you open the above door. Therefore, it is possible to steam is discharged from the heating chamber, the user is to prevent the danger of such fire wounded.

Further, the amount of steam in the heating chamber increases, and the surplus amount of steam is discharged to the outside from the exhaust port via the discharge passage and the exhaust duct. By doing so, it is possible to provide a safe steam cooker even if the user opens the door of the heating chamber by using it together with the rapid discharge of the steam in the heating chamber by opening the damper.

In the steam cooker of one embodiment,
The discharge passage is located at a higher position at the connection end with the exhaust duct than at the connection end with the heating chamber, and continues from the connection end with the exhaust duct toward the connection end with the heating chamber. that has a down slope.

According to this embodiment, when the amount of excess steam flows through the discharge passage toward the exhaust duct, the water condensed in the discharge passage flows down in the discharge passage. Guided to the heating chamber. Thus, it is possible to ing to process after completion of cooking with water generated by cooking.

In the steam cooker of one embodiment,
The aforementioned discharge passage, that provided the steam cooling means for condensing and cooling the interior of the steam.

According to this embodiment , when the excessive amount of steam flows through the discharge passage toward the exhaust duct, it passes through the discharge passage by the steam cooling means provided in the discharge passage. The steam is cooled and condensed. Accordingly, it is possible to suppress the steam that is excessive in quantity from being discharged from the exhaust port to the outside as it is .

As is clear from the above, the steam cooker of the present invention is provided with a damper for opening and closing the exhaust passage in the exhaust passage for exhausting the steam in the heating chamber to the outside, so by opening the damper , it can be rapidly and reliably discharge the vapor of the heating chamber. Therefore, the user can burst out steam when you open the door of the heating chamber, the user is to prevent the danger of such fire wounded. Furthermore, since the heating chamber and the exhaust duct are connected by the discharge passage, the amount of steam in the heating chamber increases, and the surplus amount of steam passes through the discharge passage and the exhaust duct. It can discharge | release outside from the said exhaust port.

That is, according to this invention, even if a user opens the door of the said heating chamber, a safe steam cooker can be provided.

  Hereinafter, the steam cooker of this invention is demonstrated in detail by embodiment of illustration.

  FIG. 1 is an external perspective view of a steam cooker 1 according to an embodiment of the present invention. An operation panel 11 is provided at the upper part of the front of a rectangular parallelepiped cabinet 10, and the lower side of the operation panel 11 on the front of the cabinet 10 is shown. In addition, a door 12 that rotates around the lower end side is provided. A handle 13 is provided above the door 12, and a heat-resistant glass window 14 is provided on the door 12.

  FIG. 2 is an external perspective view showing a state where the door 12 of the steam cooker 1 is opened, and a rectangular parallelepiped heating chamber 20 is provided in the cabinet 10. The heating chamber 20 has an opening 20a on the front side facing the door 12, and the side, bottom and top surfaces of the heating chamber 20 are formed of stainless steel plates. The door 12 is formed of a stainless steel plate on the side facing the heating chamber 20. A heat insulating material (not shown) is arranged around the heating chamber 20 and inside the door 12 to insulate the inside of the heating chamber 20 from the outside.

  Further, a stainless steel tray 21 is placed on the bottom surface of the heating chamber 20, and a stainless steel wire rack 24 (shown in FIG. 3) for placing an object to be heated on the tray 21 is placed. Furthermore, a substantially rectangular side-surface steam outlet 22 (only one of which is shown in FIG. 2) is provided on both side surfaces of the heating chamber 20.

  FIG. 3 is a schematic configuration diagram showing a basic configuration of the steam cooker 1. As shown in FIG. 3, the steam cooker 1 includes a heating chamber 20, a water tank 30 for storing steam water, a steam generator 40 for evaporating water supplied from the water tank 30, and the steam. A steam temperature raising device 50 for heating steam from the generator 40 and a control device 80 for controlling the steam generator 40, the steam temperature raising device 50, and the like are provided.

  A grid-like rack 24 is placed on a tray 21 placed in the heating chamber 20, and an object to be heated 90 is placed in the approximate center of the rack 24.

  In addition, a connecting portion 30 a provided on the lower side of the water tank 30 is connected to a funnel-shaped receiving port 31 a provided at one end of the first water supply pipe 31. The suction side of the pump 35 is connected to the other end of the second water supply pipe 32 that branches from the first water supply pipe 31 and extends upward, and one end of the third water supply pipe 33 is connected to the discharge side of the pump 35. . Further, a water tank water level sensor 36 is disposed at the upper end of a water level sensor pipe 38 that branches off from the first water supply pipe 31 and extends upward. Furthermore, the upper end of the air release pipe 37 branched from the first water supply pipe 31 and extending upward is connected to an exhaust duct 65 described later.

  The third water supply pipe 33 has an L shape that is bent substantially horizontally from a vertically arranged portion, and an auxiliary tank 39 is connected to the other end of the third water supply pipe 33. One end of the fourth water supply pipe 34 is connected to the lower end of the auxiliary tank 39, and the other end of the fourth water supply pipe 34 is connected to the lower end of the steam generator 40. Further, one end of a drain valve 70 is connected to the lower end of the steam generator 40 to which the fourth water supply pipe 34 is connected. One end of a drain pipe 71 is connected to the other end of the drain valve 70, and a drain tank 72 is connected to the other end of the drain pipe 71. Note that the upper portion of the auxiliary tank 39 communicates with the atmosphere via the air release pipe 37 and the exhaust duct 65.

  When the water tank 30 is connected, the water in the water tank 30 rises into the air release pipe 37 until the water level becomes the same as that of the water tank 30. Since the water level sensor pipe 38 connected to the water tank water level sensor 36 is sealed at the tip, the water level does not rise, but the pressure in the sealed space of the water level sensor pipe 38 depends on the water level of the water tank 30. Rise from atmospheric pressure. By detecting this pressure change by a pressure detection element (not shown) in the water tank water level sensor 36, the water level in the water tank 30 is detected. In the measurement of the water level when the pump 35 is stationary, the pipe 37 for opening to the atmosphere is unnecessary, but in order to prevent the suction pressure of the pump 35 from acting directly on the pressure detection element and reducing the accuracy of water level detection of the water tank 30. An open air pipe 37 having an open end is used.

  The steam generator 40 includes a pot 41 having the lower end connected to the other end of the fourth water supply pipe 34, a heater portion 42 disposed in the vicinity of the bottom surface of the pot 41, and a heater in the pot 41. It has a water level sensor 43 disposed in the vicinity of the upper side of the portion 42 and a steam suction ejector 44 attached to the upper side of the pot 41. And the fan casing 26 is arrange | positioned on the outer side of the suction inlet 25 provided in the side surface upper part of the heating chamber 20. As shown in FIG. Steam in the heating chamber 20 is sucked from the suction port 25 by the blower fan 28 disposed in the fan casing 26. The sucked steam is sent to the inlet side of the steam suction ejector 44 of the steam generator 40 through the first pipe 61 and the second pipe 62. The first pipe 61 is disposed substantially horizontally and has one end connected to the fan casing 26. The second pipe 62 is arranged substantially vertically, and has one end connected to the other end of the first pipe 61 and the other end connected to the inlet side of the inner nozzle 45 of the vapor suction ejector 44.

  The vapor suction ejector 44 includes an outer nozzle 46 that wraps the outside of the inner nozzle 45, and the discharge side of the inner nozzle 45 communicates with the internal space of the pot 41. The discharge side of the outer nozzle 46 of the vapor suction ejector 44 is connected to one end of the third pipe 63, and the vapor temperature raising device 50 is connected to the other end of the third pipe 63.

  The fan casing 26, the first pipe 61, the second pipe 62, the steam suction ejector 44, the third pipe 63, and the steam temperature raising device 50 form an external circulation path 60. One end of the discharge passage 64 is connected to the discharge port 27 provided on the lower side of the side surface of the heating chamber 20, and the other end of the discharge passage 64 is connected to one end of the exhaust duct 65. An exhaust port 66 is provided at the other end of the exhaust duct 65. A radiator 69 is externally fitted and attached to the exhaust duct 65 side of the vapor discharge passage 64. A connection portion between the first pipe 61 and the second pipe 62 forming the external circulation path 60 is connected to the exhaust duct 65 via the exhaust passage 67. A damper 68 for opening and closing the exhaust passage 67 is disposed on the connection side of the exhaust passage 67 to the first and second pipes 61 and 62.

  The steam temperature raising device 50 includes a dish-shaped case 51 disposed on the ceiling side and substantially in the center of the heating chamber 20 with the opening facing down, and a first steam heating disposed in the dish-shaped case 51. A heater 52 and a second steam heater 53 disposed in the dish-shaped case 51 are provided. The bottom surface of the dish-shaped case 51 is formed by a metal ceiling panel 54 provided on the ceiling surface of the heating chamber 20. A plurality of ceiling steam outlets 55 are formed in the ceiling panel 54. The ceiling panel 54 is finished in a dark color on the upper and lower surfaces by painting or the like. Note that the ceiling panel 54 may be formed of a metal material that changes to a dark color by repeated use or a dark-colored ceramic molded product.

  Further, the steam temperature raising device 50 is connected to one end of each of the steam supply passages 23 (only one is shown in FIG. 3) extending on the left and right sides of the heating chamber 20. The other end of the steam supply passage 23 extends downward along both side surfaces of the heating chamber 20 and is connected to side surface steam outlets 22 provided on both side surfaces and the lower side of the heating chamber 20.

  Next, the steam generator 40 will be described in detail with reference to FIGS.

  4A is a plan view of the pot 41 of the steam generator 40 as viewed from above, and FIG. 4B is a cross-sectional view of the pot 41 as viewed from line IV-IV in FIG. 4A. It is.

  As shown in FIGS. 4 (a) and 4 (b), the pot 41 is provided with a cylindrical portion 41a having a substantially rectangular horizontal plane, and an inclination that gradually decreases toward the center, provided below the cylindrical portion 41a. It has a bottom 41b made of a surface, and a water supply port 41c provided substantially at the center of the bottom 41b. The planar shape of the pot 41 has an aspect ratio of 1: 2.5, but may be an elongated shape, that is, a rectangular shape or an elliptical shape. However, the aspect ratio in the case of a rectangle is preferably 1/2, more preferably 1 / 2.5, and even more preferably 1/3 or less.

  A heater portion 42 is disposed near the bottom 41b in the pot 41. The heater portion 42 includes a first steam generating heater 42A that is a U-shaped large-diameter sheathed heater, and a U-shaped first heater 42A. The first steam generating heater 42A is configured by a second steam generating heater 42B which is a U-shaped sheathed heater having a small pipe diameter and disposed on substantially the same horizontal plane. The heater part 42 is disposed close to the side wall of the cylinder part 41a of the pot 41, and the shortest distance between the outer edge of the heater part 42 and the side wall of the cylinder part 41a is 2 mm to 5 mm. Moreover, the lower end of the heater part 42 is arrange | positioned adjacent to the bottom part 41b of the pot 41, and the shortest distance of the lowest part of the heater part 42 and the bottom part 41b of the pot 41 is 2 mm-5 mm.

  In this embodiment, the first steam generating heater 42A uses a 700 W large diameter sheathed heater, and the second steam generating heater 42B uses a 300 W small diameter sheathed heater. The first steam generating heater 42A has a curved portion 42Aa having a substantially semicircular arc shape, and two linear portions 42Ab and 42Ac extending substantially in parallel from both ends of the curved portion 42Aa. The second steam generating heater 42B has a curved portion 42Ba having a substantially semicircular arc shape and two straight portions 42Bb and 42Bc extending substantially in parallel from both ends of the curved portion 42Ba. The curved portion 42Aa of the first steam generating heater 42A has a minimum radius of curvature r1 determined by a large-diameter sheathed heater to be used, and the curved portion 42Ba of the second steam generating heater 42B has a small-tube diameter to be used. The minimum radius of curvature r2 (<r1) is determined by the sheathed heater.

  A water level sensor 43 is disposed on the side wall near the upper side of the heater part 42 in the pot 41 and on the side of the non-heat generating part (C region in FIG. 4A) inside the second steam generating heater 42B. Further, a partition plate 47 having a U-shaped cross section surrounding the water level sensor 43 is provided in the pot 41. The partition plate 47 forms a cylindrical body having a rectangular cross section with the side wall in the pot 41. The lower end of the partition plate 47 is located above the bottom 41b of the pot 41 and below the lowermost portions of the first and second steam generating heaters 42A and 42B. On the other hand, the upper end of the partition plate 47 is at least twice as high as the height from the lowermost part of the heater section 42 to the mounting position of the water level sensor 43. A temperature sensor 48 is disposed on the side wall of the pot 41 that faces the water level sensor 43.

  The water level sensor 43 is a self-heating thermistor, and in water, a temperature of about 100 ° C. to 140 ° C. is detected according to the temperature of water of 20 ° C. to 100 ° C., and in air, about 140 ° C. to about 150 ° C. Temperature is detected. Then, based on the temperature of the water detected by the temperature sensor 48, the temperature detected by the water level sensor 43 is determined, thereby determining whether or not there is water at the mounting position of the water level sensor 43. .

  FIG. 5 (a) is a side view of the steam generator 40, and FIG. 5 (b) is a sectional view taken along line VV of FIG. 5 (a).

  As shown in FIGS. 5A and 5B, a steam suction ejector 44 is attached so as to cover the upper opening of the pot 41 in which the first and second steam generating heaters 42A and 42B are arranged on the inside. The fluid (steam) flowing from the inlet 45a of the inner nozzle 45 of the vapor suction ejector 44 is discharged from the discharge port 45b of the inner nozzle 45 and discharged from the discharge port 46a of the outer nozzle 46. At this time, since the discharge side of the inner nozzle 45 communicates with the internal space of the pot 41, the saturated vapor generated in the pot 41 is drawn into the discharge port 46a side of the outer nozzle 46, and the discharge port of the inner nozzle 45 It is discharged from the discharge port 46a of the outer nozzle 46 together with the steam discharged from 45b. That is, the saturated steam at 100 ° C. and 1 atm generated by boiling the water in the pot 41 is sucked into the circulating airflow passing through the external circulation path 60 (shown in FIG. 3). Due to the structure of the steam suction ejector 44, saturated steam is quickly sucked up and no pressure is applied to the steam generator 40, so that the release of saturated steam is not hindered.

  Next, the structure of the damper 68 that opens and closes the exhaust passage 67 will be described. The damper 68 needs to be opened instantly so that the user is not exposed to steam when the door 12 is opened. In order to realize this, the damper 68 has a structure as shown in FIG. In FIG. 6, the damper 68 is provided in the exhaust duct 65. Further, the exhaust duct 65 is provided with an opening 101 to the exhaust passage 67 and an attachment portion 102 for the discharge passage 64. Reference numeral 103 denotes a case in which a damper driving device (not shown) is accommodated.

As shown in FIG. 7, the damper 68 is in close contact with the opening 101 of the exhaust duct 65 from the inside to close the opening 101, the operation plate 105 that opens and closes the door 104, and the operation It is schematically constituted by a winding spring (hereinafter simply referred to as a spring) 106 that biases the plate 105 in the opening direction. The operation plate 105 is bent and has an L-shaped cross section. The back surface side of the door portion 104 is attached to one surface 105a, and a long hole parallel to the extending direction of the surface 105a is attached to the other surface 105b. 107 and a hole 108 for attaching the spring 106 are provided. Further, a protruding surface 109 is provided in the vicinity of the bent portion on one end side of the surface 105b, and a hole 110 for inserting a rotating shaft is formed in the protruding surface 109.

  The spring 106 forms at least a single ring 106a at the central portion of the elastic metal rod, and both ends extend outward from the ring 106a to form a mounting portion 106b and a fixing portion 106c. ing. The wheel 106 a is attached and fixed by a mounting claw 111 on the opposite side of the protruding surface 109 of the operation plate 105 from the door 104 side. Further, the distal end portion of the attachment portion 106b is bent and inserted into the hole 108 provided in the surface 105b of the operation plate 105. Thus, the spring 106 is attached to the outside of the surface 105b of the operation plate 105.

  The damper 68 having the above configuration is mounted in the exhaust duct 65 as follows. A rotating shaft 112 is disposed in the lower part of the vicinity of the opening 101 to the exhaust passage 67 in parallel with the opening 101, and the hole 110 of the operating plate 105 is inserted into the rotating shaft 112 together with the ring 106 a of the spring 106. . The damper 68 opens and closes the opening 101 by rotating around the rotation shaft 112.

  The wall of the exhaust duct 65 and the wall of the case 103 for housing the damper driving device are adjacent to each other, and arc-shaped arc holes 113 and 113 ′ are formed in the both walls. The arc holes 113 and 113 ′ have a length of ¼ of an arc having a radius r with the point 114 as the center, and are arranged so as to face the slot 107 provided in the surface 105 b of the operation plate 105. ing. The damper driving device housed in the case 103 has a pin 115 that rotates on an arc having a radius r centered on the point 114. The pin 115 passes from the case 103 side through the arc hole 113 ′ on the wall of the case 103 and the arc hole 113 on the wall of the exhaust duct 65, and protrudes toward the exhaust duct 65 side. It is inserted through the hole 107. The damper driving device has a built-in motor, and the pin 115 is forcibly rotated clockwise (in the direction of the arrow (A)) by a predetermined angle on a circular arc having a radius r centered on the point 114 by driving the motor. Just rotate and stop. Further, the damper driving device incorporates a clutch mechanism (not shown) for releasing the restraint from the driving force of the motor on the pin 115 by a control signal from the control device.

  That is, in this embodiment, the damper driving device constitutes the damper opening / closing mechanism, the spring 106 constitutes the damper urging means, the motor constitutes the damper closing driving means, and the clutch mechanism This constitutes the transmission separating means.

  The damper 68 operates as follows. First, when the damper driving device is in a non-operating state, the pin 115 is in a free state, so that no driving force is applied to the damper 68 from the damper driving device. Therefore, the surface 105b of the operation plate 105 rotates around the rotation shaft 112 by the biasing force of the spring 106 in a state where the fixed portion 106c is in contact with the wall surface of the exhaust duct 65, and the door portion 104 opens the opening portion 101. To do. When the damper driving device operates in this state, the pin 115 rotates along the arcuate arc hole 113 by the driving force from the motor. Then, as the pin 115 moves, the surface 105 b of the operation plate 105 also rotates around the rotation shaft 112 against the bias by the spring 106. Thus, when the pin 115 moves on the arc of radius r centered on the point 114 by the predetermined angle, the pin 115 stops and the operation plate 105 also stops. In this state, the door 104 is in close contact with the opening 101 of the exhaust duct 65 from the inside to close the opening 101.

  Then, when the clutch mechanism is operated by the control signal from the control device, the restraint from the driving force of the motor on the pin 115 is released, and the pin 115 becomes free, the surface 105b of the operation plate 105 Is instantaneously rotated counterclockwise by the urging force of the spring 106, and the door 104 opens the opening 101.

  Next, the control block of the steam cooker 1 shown in FIG. 8 will be described.

  As shown in FIG. 8, the control device 80 includes a blower fan 28, a first steam heater 52, a second steam heater 53, a damper 68, a drain valve 70, and a first steam generator heater 42A. , Second steam generating heater 42B, operation panel 11, water tank water level sensor 36, water level sensor 43, temperature sensor 81 for detecting the temperature in heating chamber 20 (shown in FIG. 3), and heating chamber 20 A humidity sensor 82 for detecting the humidity inside the pump and a pump 35 are connected.

  The control device 80 includes a microcomputer, an input / output circuit, and the like. Based on detection signals from the water tank water level sensor 36, the water level sensor 43, the temperature sensor 81, and the humidity sensor 82, the blower fan 28 and the first steam heating unit. The heater 52, the second steam heater 53, the damper 68, the drain valve 70, the first steam generator heater 42A, the second steam generator heater 42B, the operation panel 11 and the pump 35 are controlled according to a predetermined program.

  In the steam cooker 1 configured as described above, a power switch (not shown) in the operation panel 11 is pressed to turn on the power, and the operation of the operation panel 11 starts the cooking operation. Then, the control device 80 first starts the operation of the pump 35 with the drain valve 70 closed and the exhaust passage 67 closed by the damper 68. Water is supplied into the pot 41 of the steam generator 40 from the water tank 30 through the first to fourth water supply pipes 31 to 34 by the pump 35. And if the water level sensor 43 detects that the water level in the said pot 41 reached the predetermined water level, the pump 35 will be stopped and water supply will be stopped.

  Next, the first and second steam generating heaters 42A and 42B are energized, and a predetermined amount of water accumulated in the pot 41 is heated by the first and second steam generating heaters 42A and 42B.

  Next, when the first and second steam generating heaters 42A and 42B are energized, or when the temperature of the water in the pot 41 reaches a predetermined temperature, the blower fan 28 is turned on and the steam heating device 50 is turned on. One steam heater 52 is energized. Then, the blower fan 28 sucks air (including steam) in the heating chamber 20 from the suction port 25 and sends out air (including steam) to the external circulation path 60. Since a centrifugal fan is used as the blower fan 28, a higher pressure can be generated compared to the propeller fan. Furthermore, by rotating the centrifugal fan used for the blower fan 28 at a high speed with a DC motor, the flow velocity of the circulating airflow can be extremely increased.

  Next, when the water in the pot 41 of the steam generator 40 boils, saturated steam is generated, and the generated saturated steam joins the circulating airflow passing through the external circulation path 60 at the steam suction ejector 44. The steam discharged from the steam suction ejector 44 flows into the steam temperature raising device 50 through the third pipe 63 at a high speed.

  And the steam which flowed into the said steam temperature rising apparatus 50 is heated by the 1st steam heating heater 52, and turns into a superheated steam of about 300 degreeC (it changes with cooking contents). A part of the superheated steam is ejected downward from the plurality of ceiling steam outlets 55 provided in the lower ceiling panel 54 in the heating chamber 20. Further, another part of the superheated steam is ejected from the side surface steam outlets 22 on both side surfaces of the heating chamber 20 through the steam supply passages 23 provided on both the left and right sides of the steam heating device 50.

  Thereby, the superheated steam ejected from the ceiling side of the heating chamber 20 is vigorously supplied toward the heated object 90 in the center, and the superheated steam ejected from the left and right side surfaces of the heating chamber 20 Then, the product is supplied while being lifted so as to wrap the heated object 90 from below the heated object 90. As a result, convection occurs in the heating chamber 20 in such a manner that it is blown down at the center and rises outside the center. Then, the convection steam is sequentially sucked into the suction port 25 and repeatedly circulates through the external circulation path 60 and returns to the heating chamber 20 again.

  By forming convection of superheated steam in the heating chamber 20 in this way, the superheated steam from the steam heating device 50 is sent to the ceiling steam outlet while maintaining the temperature and humidity distribution in the heating chamber 20 uniform. 55 and the side air outlet 22, and can efficiently collide with the heated object 90 placed on the rack 24. Then, the object to be heated 90 is heated by the collision of superheated steam. At this time, the superheated steam in contact with the surface of the object to be heated 90 also heats the object to be heated 90 by releasing latent heat when dew condensation occurs on the surface of the object to be heated 90. As a result, a large amount of heat of the superheated steam can be uniformly and quickly applied to the entire surface of the article 90 to be heated. Therefore, it is possible to realize cooking with no unevenness and good finish.

  Further, in the above cooking operation, when time elapses, the amount of steam in the heating chamber 20 increases, and the surplus amount of steam passes from the discharge port 27 through the discharge passage 64 and the exhaust duct 65. And discharged from the exhaust port 66 to the outside. At this time, the steam 69 passing through the discharge passage 64 is cooled and condensed by the radiator 69 provided in the discharge passage 64, thereby preventing the steam from being discharged to the outside as it is. The water condensed in the discharge passage 64 by the radiator 69 flows down in the discharge passage 64 and is guided to the receiving tray 21, and is processed together with the water generated by cooking after the cooking.

  After the cooking is finished, the control device 80 displays a cooking end message on the operation panel 11 and further sounds a signal by a buzzer (not shown) provided on the operation panel 11. Thereby, when the user who knows the end of cooking opens the door 12, the control device 80 detects that the door 12 has been opened by a sensor (not shown), and instantly opens the damper 68 of the exhaust passage 67. . Thereby, the first pipe 61 of the external circulation path 60 communicates with the exhaust duct 65 through the exhaust passage 67, and the steam in the heating chamber 20 is blown by the blower fan 28 through the suction port 25, the first pipe 61, and the exhaust passage 67. And is discharged from the exhaust port 66 through the exhaust duct 65. This damper operation is the same even if the user opens the door 12 during cooking. Therefore, the user can safely remove the object to be heated 90 from the heating chamber 20 without being exposed to steam.

  Thus, by arranging the heater part 42 in the vicinity of the bottom part 41b in the pot 41 of the steam generator 40 and on substantially the same horizontal plane, the water level supplied to the pot 41 is changed from the bottom part 41b of the pot 41. It becomes possible to be just above the upper part of the heater part 42. Accordingly, the water level in the pot 41 is set as low as possible from the bottom 41b of the pot 41 to the upper side of the upper part of the heater part 42, and the amount of water in the pot 41 heated by the heater part 42 is reduced as much as possible. The start of steam generation by the steam generator 40 can be accelerated. By raising the rise of steam generation by the steam generator 40, the rise of superheated steam can be made faster, and the cooking time can be shortened. In particular, at the time of the first heat cooking after stopping the operation for a long time, the rise of the superheated steam supplied to the heating chamber 20 can be made faster without performing preheating during the stop, so that the effect of shortening the cooking time can be obtained. It is remarkable.

  In addition, a heater section 42 is disposed in a pot 41 having an elongated planar shape (substantially rectangular in this embodiment), and the sheathed heaters (42A, 42B) used as the heater section 42 are placed in the pot 41. The area occupied by the outer edge of the heater section 42 is reduced, and the heater power for the heater occupied floor area (or water surface area) in the pot 41 can be increased. In addition, the area of the planar shape of the pot 41 can be reduced. Therefore, by increasing the heater power with respect to the heater occupation floor area (or water surface area) in the pot 41 and reducing the area of the planar shape of the pot 41 to reduce the amount of water, the steam generated by the steam generator 40 is reduced. The occurrence can be started earlier.

  Further, the first steam generating heater 42A, which is a U-shaped large-tube diameter sheathed heater, and a U-shaped small-tube diameter sheath disposed on the substantially same plane inside the first steam generating heater 42A. In the second steam generating heater 42B, which is a heater, by setting the radius of curvature of the curved portion 42Ba to the minimum radius of curvature determined by the tube diameter of the sheathed heater and the like, if the input power to the heater portion 42 is the same, The occupied area of the region surrounded by the outer edge of the heater section 42 composed of two types of sheathed heaters having different diameters is reduced so that the heater power with respect to the heater occupied floor area (or water surface area) in the pot 41 becomes the highest. The area can be increased. By increasing the heater power with respect to the heater occupation floor area (or the water surface area) in the pot 41, the start of steam generation by the steam generator can be further accelerated. In addition, the controller 80 switches between energization of the high power (700 W) first steam generating heater 42 </ b> A and the low power (300 W) second steam generating heater 42 </ b> B, so that the combination is used for generating steam. Electric power can be controlled, and steam generation according to cooking contents can be performed.

  In the above embodiment, the sheathed heater is used. However, a cartridge heater having a heating plane may be used.

  In the above embodiment, the steam generator 40 includes the first steam generating heater 42A, which is a U-shaped large-diameter sheathed heater, and the U-shaped small-tube-sized sheathed heater disposed inside thereof. Although the heater part 42 having a certain second steam generating heater 42B is used, the shape of the heater part is not limited to this, and any heater part on substantially the same horizontal plane disposed near the bottom in the pot may be used.

  For example, a shape like the heater part 90 shown in FIG. 9 may be sufficient. As shown in FIG. 9, the heater 90 includes a straight portion 90a, a semicircular arc-shaped curved portion 90b, a straight portion 90c, a semicircular arc-shaped curved portion 90d, a straight portion 90e, a curved portion 90b, The sheathed heater has a semicircular arc-shaped curved portion 90f having a radius of curvature smaller than 90d and a linear portion 90g. The radius of curvature r3 of the inner semicircular arc-shaped curved portion 90f is set to be the minimum radius of curvature of the sheathed heater. In this case, a part of the straight part 90g is located below the curved part 90d, but the main part of the heater part 90 only needs to be arranged on substantially the same horizontal plane.

  Further, the damper 68 is provided in the exhaust duct 65 and is driven to rotate by a damper driving device having a built-in motor, so that the opening 101 of the exhaust duct 65 from the inside of the exhaust duct 65 is resisted against the bias by the spring 106. Close. When the control signal from the control device 80 releases the restraint by the damper drive device, the opening 101 is instantaneously opened by the biasing force of the spring 106. Therefore, when the control device 80 detects the user's intention to open the door 12, the superheated steam in the heating chamber 20 can be discharged instantly and reliably, the superheated steam blows out of the chamber, and the user is burned. It is possible to prevent the risk of owing.

  In the above embodiment, the biasing force of the spring 106 is used as means for quickly opening the damper 68, but the invention is not particularly limited to this. For example, an electromagnetic force of a plunger can be used. It is also possible to use the shutter system or the superheated steam pressure itself.

FIG. 1 is an external perspective view of a steam cooker according to an embodiment of the present invention. FIG. 2 is an external perspective view of the steam cooker with the door opened. FIG. 3 is a schematic configuration diagram showing the configuration of the steam cooker. 4 (a) is a horizontal plan view of the pot of the steam generator of the steam cooker, and FIG. 4 (b) is a cross-sectional view of the pot 41 as seen from line IV-IV in FIG. 4 (a). FIG. 5 (a) is a side view of the steam generator 40, and FIG. 5 (b) is a cross-sectional view taken along line VV of FIG. 5 (a). FIG. 6 is a view showing a structure for attaching the damper 68 to the exhaust duct 65. FIG. 7 is a diagram showing the configuration of the damper 68. FIG. 8 is a control block diagram of the steam cooker. FIG. 9 is a plan view of a pot using another heater unit of the steam generator.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Steam cooking apparatus 11 ... Operation panel 12 ... Door 13 ... Handle 14 ... Window 20 ... Heating chamber 21 ... Receptacle 22 ... Side surface steam outlet 23 ... Steam supply passage 24 ... Rack 25 ... Inlet 26 ... Fan casing 27 ... Release Outlet 28 ... Blower fan 30 ... Water tank 31 ... First water supply pipe 32 ... Second water supply pipe 33 ... 3rd water supply pipe 34 ... 4th water supply pipe 35 ... Pump 36 ... Water tank water level sensor 39 ... Auxiliary tank 40 ... Steam Generator 41... Pot 42. Suction ejector 47 ... partition plate 48 ... temperature sensor 50 ... steam temperature raising device 51 ... dish type case 52 ... first steam heater 5 DESCRIPTION OF SYMBOLS 3 ... 2nd steam heater 60 ... External circulation path 61 ... 1st pipe 62 ... 2nd pipe 63 ... 3rd pipe 64 ... Release passage 65 ... Exhaust duct 66 ... Exhaust port 67 ... Exhaust passage 68 ... Damper 69 ... Radiator 70 DESCRIPTION OF SYMBOLS ... Drain valve 71 ... Drain pipe 72 ... Drain tank 80 ... Control apparatus 81 ... Temperature sensor 82 ... Humidity sensor 90 ... Heater part 90a, 90c, 90e, 90g ... Linear part 90b, 90d, 90f ... Curved part 101 ... Opening part 103 ... Damper driving device storage case 104 ... Door part 105 ... Operating plate 106 ... Spring 107 ... Elongated hole 112 ... Rotating shaft 113 ... Arc hole 115 ... Pin

Claims (3)

A steam generator for generating steam;
A heating chamber for heating an object to be heated by steam supplied from the steam generator;
An exhaust passage for discharging the steam in the heating chamber to the outside;
A damper for opening and closing the exhaust passage;
An exhaust duct for guiding the steam discharged through the exhaust passage as the damper is opened to the exhaust port;
A steam cooker, comprising: a discharge passage that connects the heating chamber and the exhaust duct and guides surplus steam in the heating chamber to the exhaust duct . The steam cooker according to claim 1, wherein
The discharge passage is located at a higher position at the connection end with the exhaust duct than at the connection end with the heating chamber, and continues from the connection end with the exhaust duct toward the connection end with the heating chamber. A steam cooker having a downward slope . The steam cooker according to claim 1 or 2 ,
A steam cooker, wherein the discharge passage is provided with steam cooling means for cooling and condensing the steam inside .

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