JP2015198756A - Shelf structure for steam sterilization and steam sterilizer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accelerate drying in the subsequent step by accumulating heat in a shelf board in a sterilization step to reduce the drying time.SOLUTION: A shelf 1 is arranged in a sterilization tank of a steam sterilizer or taken into and out of the sterilization tank, is composed of aluminum or an aluminum alloy or a magnesium alloy and includes a shelf plate 12 on which a to-be-sterilized object is mounted and a water reception plate 13 which is provided in the lower part of the shelf plate 12 and prevents falling of condensed water onto the object on another shelf plate 12 located thereunder from the shelf plate 12. The shelf plate 12 is preferably provided with an irregularity 17 in the lower surface so that the surface area of the upper surface is larger than that of the lower surface. The shelf plate 12 is preferably formed with an appropriate through hole 16 so that condensed water does not reside on the upper surface.

Description

  The present invention relates to a shelf provided in a sterilization tank of a steam sterilizer or a shelf to be taken in and out of the sterilization tank. Moreover, it is related with the steam sterilizer by which such a shelf is provided or such a shelf is taken in and out.

  Conventionally, as disclosed in Patent Document 1 below, a shelf (13) formed by a combination of wires or a perforated plate and on which an object to be sterilized is placed, and a condensed water of steam provided at the lower portion of the shelf are provided. There is known a shelf structure for steam sterilization that includes a fall prevention plate (14) that prevents the lower shelf material from falling onto an object to be sterilized, and the fall prevention plate (14) is made of aluminum.

JP 2010-246847 A

  In any conventional shelf structure for steam sterilization, the shelf material on which an article to be sterilized is placed is made of a stainless steel net or plate. However, stainless steel has lower specific heat and thermal conductivity than aluminum, for example.

  When the specific heat is small, the amount of condensed water generated in the shelf material is small in the sterilization process. When the shelf material is plate-shaped, the condensed water stays on the top surface of the shelf material (condensed water generated on the top surface of the shelf material and the object to be sterilized). The ratio of condensed water falling from the shelf material (condensed water generated on the side surface and the lower surface of the shelf material) is reduced. If this ratio is small, the amount of heat stored in the shelf material is used to re-evaporate the condensed water on the shelf material by reducing the pressure in the drying process after the sterilization process, and to further dry the sterilized material. Can not. In other words, since the amount of heat stored in the shelf material is small, the amount of heat is only offset by the evaporation of the condensed water on the shelf material, and there is not enough heat to dry the items to be sterilized, shortening the drying time. I ca n’t plan. On the other hand, even if the shelf material is formed relatively thick in order to store heat on the shelf material, if the thermal conductivity is small, during the drying process, the heat flux that gives the shelf material heat storage to the sterilized material becomes small, The drying time cannot be shortened. Therefore, it is preferable that the shelf material has a high specific heat and a large heat flux (in other words, thermal conductivity).

  In addition, the net-structured shelf material has a small heat transfer surface to an object to be sterilized, which is disadvantageous for sterilization and drying. On the other hand, a shelf with a plate structure receives a lot of heat of condensation in the sterilization process, but condensate tends to remain on the plate, and heat is used to re-evaporate the residual condensate during decompression in the drying process. The drying time of sterilized products cannot be shortened.

  Therefore, the problem to be solved by the present invention is to provide a shelf structure for steam sterilization and steam sterilization that can accelerate drying in the subsequent drying process by accumulating heat on the shelf board in the sterilization process and shorten the drying time. Is to provide a vessel.

  The present invention has been made to solve the above-mentioned problems, and the invention according to claim 1 is a shelf provided in a sterilization tank of a steam sterilizer, or a shelf that is taken in and out of the sterilization tank, It is made of a material having a specific heat of 0.8 kJ / (kg · K) or more and a thermal conductivity of 90 W / (m · K) or more, and a shelf board on which an object to be sterilized is placed and a lower part of the shelf board. A steam sterilization shelf structure comprising: a water receiving plate that prevents the condensed water from the shelf plate from falling on an object to be sterilized on the lower shelf plate.

  According to the first aspect of the present invention, the shelf board is formed using a material having a larger specific heat and thermal conductivity than stainless steel, and the water receiving plate is provided at the lower part of the shelf board. By preventing the condensed water from falling on the object to be sterilized on the lower shelf, sterilization and drying can be achieved quickly. In particular, drying time can be shortened by storing heat on the shelf board in the sterilization process and performing the subsequent drying process.

  The invention according to claim 2 is the shelf structure for steam sterilization according to claim 1, wherein the material is aluminum, an aluminum alloy, or a magnesium alloy.

  According to invention of Claim 2, since the shelf board was comprised using aluminum or an aluminum alloy, or a magnesium alloy, it heat-stores on a shelf board in a sterilization process, and drying time is performed by performing a subsequent drying process. Can be shortened.

  The invention according to claim 3 is characterized in that the shelf plate is formed with irregularities or fins on the lower surface so that the surface area of the lower surface is larger than the upper surface. 2. The shelf structure for steam sterilization according to 2.

  According to the third aspect of the present invention, a large amount of condensed water is generated from the upper surface to the lower surface of the shelf board, and the ratio of the condensed water falling from the shelf material is increased as compared with the condensed water staying on the shelf material. Since water is not dropped onto the object to be sterilized by the water receiving plate, the shelf board is heated quickly while suppressing the generation of condensed water on the top surface of the shelf board, so that the object to be sterilized can be heated and then dried quickly. Can be planned.

  The invention according to claim 4 is characterized in that the shelf plate is provided with a groove or a hole on the upper surface and / or inclined so as to allow the condensed water to fall downward. The shelf structure for steam sterilization according to any one of claims 1 to 3.

  According to the fourth aspect of the present invention, grooves and holes are formed in the shelf board, or the shelf board is inclined to prevent the condensate from staying on the upper surface of the shelf board, Heating and subsequent drying can be achieved quickly.

The invention according to claim 5 is the steam sterilization shelf according to any one of claims 1 to 4, wherein the water receiving plate is any one of the following (a) to (c). Structure.
(A) A water receiving plate formed in a V shape or an inverted V shape.
(B) A water receiving plate formed in a quadrangular pyramid shape or an inverted quadrangular pyramid shape.
(C) A water receiving plate disposed with the plate material inclined.

  According to invention of Claim 5, a water receiving plate can be manufactured cheaply with a simple structure.

  According to a sixth aspect of the present invention, the sterilization tank of the steam sterilizer is provided with heating surfaces on the left and right sides, and the water receiving plate is formed in a V shape or an inverted V shape having inclined surfaces on the left and right sides. The shelf structure for steam sterilization according to claim 5.

  According to invention of Claim 6, the inclined surface of a water receiving plate tends to receive a radiant heat from a sterilization tank, and also tends to radiate the radiant heat also to a shelf board. Thereby, heating of a shelf board can be aimed at rapidly.

  Invention of Claim 7 is a steam sterilizer in which the shelf of the shelf structure for steam sterilization of any one of Claims 1-6 is provided, or such a shelf is taken in and out, Comprising: In the drying step after the process, after depressurizing the inside of the sterilization tank, the depressurization is stopped, steam is supplied into the sterilization tank to heat the shelf, and then the steam supply is stopped. The steam sterilizer is characterized in that the inside of the sterilization tank is decompressed again.

  According to invention of Claim 7, it can be set as the steam sterilizer which has an effect by the shelf structure for steam sterilization described in each said claim. Moreover, in the middle of the drying process, steam is temporarily supplied into the sterilization tank to heat the shelf board, so that the shelf board can be reheated and the drying time can be shortened.

  Furthermore, the invention according to claim 8 is a steam sterilizer in which the shelf of the shelf structure for steam sterilization according to any one of claims 1 to 6 is provided, or such a shelf is taken in and out. In the air evacuation process before the sterilization process, or in the drying process after the sterilization process, with the air in the sterilization tank, steam is supplied into the sterilization tank to heat the shelf, and then the steam The steam sterilizer is characterized in that the inside of the sterilization tank is depressurized while supply is stopped.

  According to invention of Claim 8, it can be set as the steam sterilizer which has an effect by the shelf structure for steam sterilization described in each said claim. In addition, in the state where there is air in the sterilization tank and the object to be sterilized, steam is temporarily supplied to the sterilization tank and the shelf board is heated to inhibit condensation heat transfer to the object to be sterilized with air. Therefore, it is possible to store heat on the shelf board while reducing the condensed water generated in the sterilized material, and to dry the sterilized material more advantageously.

  According to the shelf structure for steam sterilization and the steam sterilizer of the present invention, by storing heat on the shelf plate in the sterilization process, drying in the subsequent drying process can be promoted and the drying time can be shortened.

It is the schematic side view which showed the state with which the inner trolley | bogie which has the shelf to which the shelf structure for steam sterilization of one Example of this invention was applied was taken in / out by the outer trolley | bogie and a sterilization tank. It is a schematic perspective view which shows the state in which the inner trolley | bogie was mounted on the outer trolley | bogie of FIG. It is a schematic perspective view which shows the state which looked at the shelf board of the inner trolley | bogie of FIG. 2 from the downward direction. It is the schematic which shows the relationship between the pressure in the sterilization tank during operation | movement of the steam sterilizer of this invention, and elapsed time, and has shown only the principal part.

  Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows an inner carriage 2 having a plurality of upper and lower shelves 1 on which an object to be sterilized (not shown) is placed, an outer carriage 3 on which the inner carriage 2 is placed and transported, and an inner carriage 3 between the inner carriage 2 and the outer carriage 3. It is a schematic side view which shows the steam sterilizer 4 with which the trolley | bogie 2 is taken in and out. The article to be sterilized may be accommodated in a sterilization bag, non-woven fabric, or sterilization container.

  The inner carriage 2 is carried on the outer carriage 3 and is moved between the outer carriage 3 and the sterilization tank 5 and put in and out. For this purpose, the steam sterilizer 4 is provided with a guide rail 6 at the bottom of the sterilization tank 5, and the wheels 7 of the inner carriage 2 travel on the guide rail 6. The outer carriage 3 is also provided with a guide rail 9 on the pedestal 8, and the wheels 7 of the inner carriage 2 travel on the guide rail 9. The outer carriage 3 is allowed to travel by a caster 10 provided at the bottom of the base 8. The outer carriage 3 is provided with a handle 11, and the outer carriage 3 can be driven with the handle 11.

  The steam sterilizer 4 is an apparatus that supplies steam into the sterilization tank 5 to sterilize an object to be sterilized in the sterilization tank 5. The steam sterilizer 4 of this embodiment is sterilized by opening to the front (right side in FIG. 1) and opening and closing the opening by a door, and sucking and discharging the gas in the sterilization tank 5 to the outside. Depressurization means (not shown) for depressurizing the inside of the tank 5, return pressure means (not shown) for returning the inside of the sterilization tank 5 by introducing outside air into the depressurized sterilization tank 5, and steam into the sterilization tank 5 Steam supply means (not shown) for supply, drain discharge means (not shown) for discharging condensed water from the sterilization tank 5 through a steam trap, and the gas in the sterilization tank 5 from the atmospheric pressure by external pressure Exhaust means (not shown) that leads to the sterilization tank 5, a pressure sensor (not shown) that detects the pressure in the sterilization tank 5, a temperature sensor (not shown) that detects the temperature in the sterilization tank 5, and detection signals of these sensors Control means (not shown) for controlling each means based on the above.

  The steam sterilizer 4 evacuates the air from the sterilization tank 5, supplies steam (usually saturated steam) into the sterilization tank 5 to sterilize the sterilization target, and then sterilizes the sterilization tank 5. Depressurize to dry the object to be sterilized. Exclusion of air from the sterilization tank 5 is typically performed by repeatedly reducing the pressure in the sterilization tank 5 by the decompression means and steaming the sterilization tank 5 by the steam supply means. Thereafter, the inside of the sterilization tank 5 is pressurized with steam by means of steaming, and the sterilization tank 5 is raised to the sterilization temperature (typically 135 ° C.), and then the sterilization process is started. In the sterilization process, the temperature in the sterilization tank 5 is monitored by a temperature sensor, and the steam supply into the sterilization tank 5 by the steam supply means is controlled so that the sterilization temperature is maintained for the sterilization time. Thereafter, the steam supply by the steam supply means is stopped, the steam is exhausted from the sterilization tank 5 by the exhaust means, the pressure inside the sterilization tank 5 is reduced to a predetermined pressure by the pressure reduction means, and the set time is maintained. Try to dry things. Although details will be described later, in this drying step, steam may be temporarily supplied into the sterilization tank 5 by steam supply means. After the object to be sterilized is dried, the decompression means is stopped, while the inside of the sterilization tank 5 is decompressed to atmospheric pressure by the decompression means, and the series of operations is completed.

  As described above, the steam sterilizer 4 sequentially executes the air exclusion process, the sterilization process, the exhaust process, and the drying process. The steam sterilizer 4 includes heating surfaces on the left and right sides of the sterilization tank 5 in order to heat the inside of the sterilization tank 5 from the outside and maintain the desired temperature. Typically, the left and right side walls of the sterilization tank 5 are provided with steam jackets (not shown) that supply steam in a hollow structure. As a preheating step before the air exclusion step, steam is supplied to the steam jacket to preheat the sterilization tank 5. And the heating and holding in the sterilization tank 5 by such a steam jacket is continuously performed from the subsequent air exclusion process to the drying process. Therefore, in the sterilization process and the drying process, the article to be sterilized is heated from the steam jacket.

  FIG. 2 is a schematic perspective view showing a state where the inner carriage 2 is placed on the outer carriage 3. As described above, the inner carriage 2 is placed on the outer carriage 3 and can be transported, and is taken in and out between the outer carriage 3 and the sterilization tank 5. The inner cart 2 includes a plurality of shelves 1 in the vertical direction, and the shelf structure for steam sterilization of the present invention is applied to one or a plurality of shelves 1. Here, the shelf structure for steam sterilization of the present invention is applied to all the shelves 1, but it is not necessary to install a water receiving plate 13 to be described later on the lowermost shelf 1. 1 and 2, the three shelves 1 are provided at the top and bottom, but it goes without saying that the number of the shelves 1 can be changed as appropriate.

  The inner bogie 2 is provided with support columns 14 along the vertical direction at the four corners of the front, rear, left, and right, and a plurality of shelves 1 are held on these support columns 14 at intervals in the vertical direction. At this time, each shelf 1 is provided on the shelf 12 on which the article to be sterilized is placed and the lower part of the shelf 12, and the condensed water from the shelf 12 and the article to be sterilized is placed on the lower shelf 12 and the article to be sterilized. And a water receiving plate 13 for preventing falling into a sterilized product. However, as described above, only the shelf 12 is provided in the lowest shelf 1 and the installation of the water receiving plate 13 can be omitted.

  As will be described later, the shelf board 12 is formed of a material excellent in heat storage, and the material of the support column 14 and the water receiving plate 13 is not particularly limited. The support column 14 is made of, for example, stainless steel, and the water receiving plate 13 is made of, for example, stainless steel, aluminum, or synthetic resin.

  The shelf plate 12 is held on the support column 14 by an appropriate method, and the water receiving plate 13 is held on the shelf plate 12 or the support column 14 by an appropriate method. For example, pipes 15 are fixed to the four corners of the shelf board 12 and the water receiving plate 13, respectively, and the pipes 15 are fitted to the columns 14 and fixed to a desired height. However, the shelf plate 12 and the water receiving plate 13 may be fixed to the common pipe 15 at each of the four corners, and the shelf plate 12 and the water receiving plate 13 may be handled as an integral unit. Further, the inner carriage 2 may be assembled while the pipes 15 provided at the four corners of the shelf plate 12 and the water receiving plate 13 constitute a part of the column 14. Furthermore, the four corners of the shelf plate 12 and the water receiving plate 13 may be simply welded to the support column 14 of the inner carriage 2 or hooked on hooks provided on the support column 14. In addition, the water receiving plate 13 may be held on the column 14 via the shelf plate 12 by holding the water receiving plate 13 on the shelf plate 12.

  The shelf board 12 is formed from the material excellent in heat storage property compared with the conventional stainless steel. Specifically, it is configured using a material having a specific heat of 0.8 kJ / (kg · K) or more and a thermal conductivity of 90 W / (m · K) or more. For example, aluminum or an aluminum alloy, or a magnesium alloy.

The specific heat [kJ / (kg · K)] and thermal conductivity [W / (m · K)] of stainless steel, aluminum, aluminum alloy, and magnesium alloy are as follows.
Stainless steel has a specific heat of 0.46 to 0.494 and a thermal conductivity of 13 to 16.
Aluminum has a specific heat of 0.90 and a thermal conductivity of 204.
Aluminum alloy 7075 has a specific heat of 0.96 and a thermal conductivity of 120.
Magnesium alloy AZ31 has a specific heat of 0.96 and a thermal conductivity of 96.

  As is clear from this, in the case of aluminum, for example, the specific heat can be increased by about twice and the thermal conductivity can be increased by about 10 times compared to stainless steel. Since specific heat is large, heat storage is excellent. Therefore, heat can be stored in the shelf 12 in the sterilization process, and the heat to be sterilized can be heated by the heat of the shelf 12 in the drying process by releasing the heat storage in the subsequent drying process, so that the drying time can be shortened. it can. In addition, since the thermal conductivity is large, the heat flux that gives the stored heat of the shelf board 12 to the sterilized object during the drying process increases, and from this point, the drying time can be shortened.

  As described above, the shelf board 12 is configured using aluminum, an aluminum alloy, or the like, and in this case, the metal may be subjected to anticorrosion treatment. For example, alumite-treated aluminum can be used as aluminum.

  FIG. 3 is a perspective view showing a state in which the shelf board 12 of this embodiment is viewed from below. The shelf plate 12 may be a simple flat plate, but it is preferable that the lower surface is provided with irregularities or fins so that the surface area of the lower surface is larger than the upper surface. The shapes and positions of the irregularities and fins are set as appropriate. In this embodiment, as shown in FIG. 2 and FIG. 3, the shelf board 12 is an average that takes into account the presence of a through-hole 16 to be described later (that is, the portion of the through-hole 16 is filled with meat at other locations). It is formed from a relatively thick plate material having a thickness of 4 mm or more (for example, width 600 mm × length 1200 mm × thickness 8 mm, made of 15 to 16 kg / sheet of aluminum), and the upper surface is formed flat, while jagged irregularities 17 are formed on the lower surface. Is formed. In the case of the illustrated example, grooves 17 having a substantially triangular cross section are formed at equal intervals in the left-right direction (the width direction of the shelf board) along the front-rear direction (the longitudinal direction of the shelf board) on the lower surface of the shelf board. . However, the grooves 17 formed on the bottom surface of the shelf board 12 may be formed along the left-right direction at equal intervals in the front-rear direction, and are not limited to being parallel or perpendicular to the long side of the shelf board 12 and are arranged obliquely. May be. Further, in the case where a fin is provided instead of or in addition to the unevenness 17, the fin may be provided so as to extend downward on the lower surface of the shelf plate 12.

  By increasing the surface area of the lower surface from the upper surface, the shelf board 12 can generate a large amount of condensed water from the upper surface to the lower surface in the sterilization process. In other words, the shelf board 12 receives a lot of heating from the lower surface. Moreover, the condensed water is not dropped on the lower shelf board 12 or its sterilized object by the water receiving plate 13 provided at the lower part of the shelf board 12. Thereby, while suppressing the generation | occurrence | production of the condensed water in the upper surface of the shelf board 12, the shelf board 12 can be heated rapidly and the to-be-sterilized thing and subsequent drying can be aimed at rapidly.

  The shelf plate 12 is preferably provided with a groove or a hole on the upper surface and / or an inclined surface so that the condensed water is dropped downward. In this embodiment, a plurality of elongated through holes 16 extending in the left-right direction are formed in the horizontal shelf 12 at equal intervals in the front-rear direction. However, the through holes 16 may be formed along the front-rear direction at equal intervals on the left and right sides, and may be appropriately changed, such as being not limited to being perpendicular or parallel to the long side of the shelf board 12 and may be disposed obliquely. Is possible.

  When a groove is formed on the upper surface of the shelf board 12 instead of the through hole 16, the condensed water can be drained outside the shelf board 12 by opening the groove at one or more edges of the shelf board 12. Alternatively, it is preferable to allow the condensed water to be drained downward from the inside of the groove by forming a downward drainage hole at an appropriate location at the bottom of the groove. And in order to drain smoothly to an edge or a drain hole, it is good to form the bottom of a slot in an inclined surface, or to arrange shelf 12 in a slant.

  In any case, by forming grooves and holes in the shelf plate 12 to prevent the condensate from staying on the top surface of the shelf plate, the object to be sterilized can be quickly heated and then dried. In addition, instead of or in addition to forming grooves and holes in the shelf board 12, the shelf board 12 itself may be inclined to drain condensed water from the top surface of the shelf board 12. At this time, it goes without saying that the inclination angle of the shelf board 12 is such an inclination that the article to be sterilized on the shelf board 12 does not slide down.

  The water receiving plate 13 is provided in the lower part of the shelf board 12 and prevents the condensed water from the shelf board 12 from falling on the lower shelf board 12 or an object to be sterilized. The shape of the water receiving plate 13 is not particularly limited, but is typically a quadrangular plate material, and the four corners thereof are held by the support column 14 or the shelf plate 12 immediately above. The water receiving plate 13 is preferably formed to be the same as or larger than the shelf plate 12 in plan view. The water receiving plate 13 is provided so as to be superimposed immediately below each shelf plate 12 excluding the lowest shelf plate 12. For example, the water receiving plate 13 can have any of the following configurations.

  (A) The water receiving plate 13 is formed from an inverted V-shaped (that is, mountain-shaped) quadrangular plate material in a front view or a side view. Thereby, an inclined surface is arrange | positioned at right and left or front and back, and condensed water can be flowed down to right and left both sides or both front and rear along the inclined surface. At this time, the top portion (bending portion) of the inverted V shape does not necessarily need to be arranged along the front-rear direction or the left-right direction, and may be arranged inclined with respect to them (for example, inclined rightward as going backward). Good. In addition, the left and right or front and rear inclined surfaces may be formed so as to incline downward as they go in one or both of the longitudinal directions of the lower end side, in addition to the lower end side being horizontally disposed. The condensed water can be dropped downward from the corners of the plate 13.

  (B) The water receiving plate 13 is formed from a V-shaped (that is, valley-shaped) quadrangular plate material in a front view or a side view. Thereby, an inclined surface is arrange | positioned at right and left or front and back, Condensed water can be collected in a V-shaped groove part (bending part) along the inclined surface, and can be poured down to the longitudinal direction one or both of the groove part. At this time, the V-shaped groove portions are not necessarily arranged along the front-rear direction or the left-right direction, and may be arranged inclined with respect to them (for example, inclined rightward as going backward). In addition, the left and right or front and rear inclined surfaces may be formed so as to incline downward as going to one or both of the longitudinal directions of the lower end side, in addition to the lower end side (V-shaped groove) being horizontally disposed. In that case, drainage from the water receiving plate 13 can be performed more smoothly.

  (C) The water receiving plate 13 is formed in a quadrangular pyramid shape. In this case, inclined surfaces are arranged on the front, rear, left, and right, and the condensed water can flow down from front to back and left and right.

  (D) The water receiving plate 13 is formed in an inverted quadrangular pyramid shape. In this case, the water collected at the central portion (downward top) by the inclined surface is led out of the shelf board and drained by a hose or the like.

  (E) The water receiving plate 13 is formed from a flat plate arranged in an inclined manner. For example, a rectangular flat plate may be tilted to the left or right or to the front or back. Thereby, condensed water can be poured down along an inclined surface. In addition, by forming so that one corner | angular part may be arrange | positioned most downward, condensed water can be dropped from the corner | angular part below.

  According to the shelf structure for steam sterilization of the present embodiment, the shelf plate 12 having excellent heat storage performance and the condensed water generated on the shelf plate 12 are not dropped to the lower stage (accepted or passed to the outside of the inner carriage 2 or the like). ) Steam sterilization and subsequent drying can be performed quickly and reliably by the water receiving plate 13. In particular, since the shelf board 12 is excellent in heat storage, it can be heated and stored by steam in the sterilization process, and heat can be released in the drying process to heat the object to be sterilized, so that the drying time can be shortened. Moreover, the shelf 12 is heated by receiving a large amount of steam condensation heat on the lower surface with a large surface area, and the condensate does not accumulate because holes 16 and grooves are formed or inclined on the upper surface. The sterilized product can be quickly dried. By not leaving the condensed water on the shelf board 12, it is possible to prevent the heat storage of the shelf board 12 from being used for re-evaporation of the remaining condensed water in the drying process, and to effectively heat the object to be sterilized. . In this way, the drying time can be shortened by 10 to 60 minutes compared to the case of a conventional stainless steel net shelf.

  FIG. 4 is a schematic diagram showing the relationship between the pressure P in the sterilization tank 5 during the operation of the steam sterilizer of the present invention and the elapsed time t, and shows only the main part. As shown in this figure, after completion of the sterilization step S1, the exhaust step S2 from the inside of the sterilization tank 5 is performed, and then the inside of the sterilization tank 5 is decompressed by the decompression means to execute the drying process S3 of the sterilization object. In the drying step S3, as shown in the figure, steam may be temporarily supplied into the sterilization tank 5 to heat the shelf 12 and re-store heat. That is, as the drying step S3 after the sterilization step S1, the inside of the sterilization tank 5 is depressurized (for example, P2 = -95 to -98 kPa), and then the decompression is stopped and steam is supplied into the sterilization tank 5. After the shelf 12 is heated and held for a predetermined time (a time during which heat can be stored in the shelf 12, for example, 3 to 5 minutes), the inside of the sterilization tank 5 may be decompressed again with the steam supply stopped. Further, as indicated by a two-dot chain line, such an operation may be repeated a plurality of times. That is, the operation of temporarily supplying steam into the sterilization tank 5 may be performed a plurality of times during the drying step S3. In the present embodiment, the steaming during the drying step S3 is performed up to the same sterilization pressure (sterilization temperature) P1 in the sterilization step S1, but in some cases, a lower pressure may be used.

  Moreover, in the air exclusion process before the sterilization process S1 or the drying process S3 after the sterilization process S1, with the air in the sterilization tank 5, steam is supplied into the sterilization tank 5 to heat the shelf 12; Thereafter, the inside of the sterilization tank 5 may be depressurized in a state where the steam supply is stopped, and the process may be returned to the above-described normal air exclusion process or drying process. In other words, during the air exhausting process or the drying process, with the air in the sterilization tank 5 temporarily, steam is supplied into the sterilization tank 5 to heat the shelf 12 and then the steam is supplied. You may perform operation which decompresses the inside of the sterilization tank 5 in the state which stopped. In this case, in the state where air is present in the sterilization tank 5 and thus the object to be sterilized, steam is temporarily supplied into the sterilization tank 5 to heat the shelf board 12, thereby condensing heat transfer to the object to be sterilized. Since air is inhibited by air, heat can be stored in the shelf board 12 while reducing condensed water generated in the object to be sterilized, and the object to be sterilized can be dried more advantageously. In order to secure air in the sterilization tank 5, it is only necessary to introduce the outside air into the sterilization tank 5 by the decompression means after reducing the pressure in the sterilization tank 5 by the decompression means in the air exclusion process or the drying process. This operation can be omitted in the situation where air still exists in the sterilization tank 5 for the air exclusion process.

  By the way, in drying process S3, although the inside of the sterilization tank 5 is heated by heating surfaces, such as a steam jacket provided in the right and left in the sterilization tank 5, the water receiving plate 13 is easy to receive the heat radiation from the heating surface. preferable. Specifically, considering that there are heating surfaces on the left and right in the sterilization tank 5, the water receiving plate 13 is preferably formed in a V-shape or an inverted V-shape with inclined surfaces on the left and right. Moreover, it is preferable to form the material with a high thermal emissivity. Thereby, the water receiving plate 13 receives the heat radiation from the heating surface, and further radiates the heat to the shelf board 12 to heat the shelf board 12 and thereby to heat the object to be sterilized.

  The shelf structure for steam sterilization and the steam sterilizer 4 of the present invention are not limited to the configuration of the above-described embodiment, and can be changed as appropriate. In particular, a shelf board 12 made of a material having a specific heat of 0.8 kJ / (kg · K) or more and a thermal conductivity of 90 W / (m · K) or more, on which an article to be sterilized is placed, If it is provided with the water receiving plate 13 provided in the lower part and preventing the condensed water from the shelf 12 falling to the to-be-sterilized thing of the lower shelf 12, the shelf structure is changed appropriately. Is possible.

  For example, in the above embodiment, the article to be sterilized is placed on the inner carriage 2 and the inner carriage 2 is put in and out between the sterilization tank 5 and the outer carriage 3, but the outer carriage 3 is omitted and the inner carriage 2 is used alone. As a sterilization cart, the sterilization tank 5 may be directly put in and out by a caster. Alternatively, the sterilization tank 5 itself may be provided with a shelf 1 (shelf plate 12 and water receiving plate 13), and an object to be sterilized may be directly taken into and out of the shelf 1. In that case, it replaces with the said support | pillar 14, and the shelf board 12 and the water receiving plate 13 can also be attached using the side wall in the sterilization tank 5, or a member fixed to it.

  Moreover, in the said Example, although the shelf board 12 was formed from aluminum, an aluminum alloy, or a magnesium alloy, you may be comprised combining the some member of these materials. Moreover, you may use for some members the member comprised by members other than these materials depending on the case. For example, the four corners of a stainless steel frame material may be attached to the support column 14, and an aluminum plate material may be fitted into the frame to constitute the shelf board 12. At this time, the inside of the frame may be divided into a plurality of parts, and aluminum plate materials may be fitted into the divided parts. Further, the shelf plate 12 may be configured by incorporating an aluminum plate material into a stainless steel net shelf, such as placing an aluminum plate material on a stainless steel net shelf.

  Furthermore, copper having high thermal conductivity may be polymerized on the upper surface of the shelf board 12 made of aluminum, aluminum alloy, magnesium alloy or the like. For example, when anodized aluminum is used, sliding the sterilization container on the upper surface of the aluminum may cause the anodized to peel off, and the aluminum may turn black or brown when exposed to high temperature steam. In addition, copper may be bonded to the upper surface of the shelf board 12.

  In addition, the shelf board 12 is good also as a vacuum vessel structure which has water inside. In that case, the water in the hollow part of the shelf board 12 is evaporated in the sterilization process, and the object to be sterilized is heated by the condensation latent heat in the drying process.

DESCRIPTION OF SYMBOLS 1 Shelf 2 Inner trolley 3 Outer trolley 4 Steam sterilizer 5 Sterilization tank 6 Guide rail (of sterilization tank) 7 Wheel 8 Base 9 (Outer carriage) Guide rail 10 Caster 11 Handle 12 Shelf plate 13 Water receiving plate 14 Strut 15 Pipe 16 holes 17 irregularities (grooves)

Claims (8)

A shelf provided in a sterilization tank of a steam sterilizer, or a shelf to be taken in and out of the sterilization tank,
A shelf board with a specific heat of 0.8 kJ / (kg · K) or higher and a thermal conductivity of 90 W / (m · K) or higher, on which an object to be sterilized is placed;
A shelf structure for steam sterilization, comprising: a water receiving plate provided at a lower portion of the shelf plate for preventing the condensed water from the shelf plate from falling on an object to be sterilized on the lower shelf plate. The shelf structure for steam sterilization according to claim 1, wherein the material is aluminum, an aluminum alloy, or a magnesium alloy. The shelf structure for steam sterilization according to claim 1 or 2, wherein the shelf plate is provided with irregularities or fins on the lower surface so that the surface area of the lower surface is larger than the upper surface. . 4. The shelf according to claim 1, wherein a groove or a hole is formed on the upper surface and / or is inclined so that the condensed water is dropped downward. The shelf structure for steam sterilization according to item 1. The shelf structure for steam sterilization according to any one of claims 1 to 4, wherein the water receiving plate is any one of the following (a) to (c).
(A) A water receiving plate formed in a V shape or an inverted V shape.
(B) A water receiving plate formed in a quadrangular pyramid shape or an inverted quadrangular pyramid shape.
(C) A water receiving plate disposed with the plate material inclined. The sterilization tank of the steam sterilizer has heating surfaces on the left and right,
The shelf structure for steam sterilization according to claim 5, wherein the water receiving plate is formed in a V shape or an inverted V shape in which inclined surfaces are arranged on the left and right. A steam sterilizer in which a shelf of the shelf structure for steam sterilization according to any one of claims 1 to 6 is provided, or such a shelf is taken in and out,
In the drying step after the sterilization step, after the pressure inside the sterilization tank is reduced, the pressure is stopped, the steam is supplied into the sterilization tank and the shelf is heated, and then the steam supply is stopped. The steam sterilizer is characterized in that the inside of the sterilization tank is depressurized again. A steam sterilizer in which a shelf of the shelf structure for steam sterilization according to any one of claims 1 to 6 is provided, or such a shelf is taken in and out,
In the air evacuation process before the sterilization process or the drying process after the sterilization process, with the air in the sterilization tank, steam is supplied into the sterilization tank to heat the shelf, and then the steam supply The steam sterilizer is characterized in that the inside of the sterilization tank is depressurized in a state where the operation is stopped.

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