Food material powder supply device

Abstract

A food material powder supply device is provided with a filter device for cooling food material powder in a supply tank by means of latent heat of evaporation by vacuumizing the supply tank. The food material powder supply device of the present invention operates a water-seal vacuum pump in an early stage of a vacuumizing period, switches to an oil rotary vacuum pump in a later stage of the vacuumizing period, and operates a gas supply device at a prescribed timing in the later stage to supply external gas to the filter medium from a position as close as possible to a guide outlet of the filter device during the vacuumizing process, and removes food material powder adhering to the filter medium into the supply tank by means of external gas expanded due to a pressure difference.

Description

Technical Field

[0001] This invention relates to a feeding device for food material powder. More particularly, this invention relates to a feeding device for food material powder that includes at least a cooling mechanism for cooling the powder. Background Technology

[0002] The following factory-type food material supply system is known: Particulate food powder or small granular food materials are stored in a storage tank. After being taken from the storage tank and measured, a predetermined amount of food material is transferred to a supply tank for temporary storage. Then, at predetermined times, the food material is supplied from the supply tank to food processing machinery such as mixers, kneaders, agitators, or pulverizers. Here, the particulate food powder includes wheat flour, barley flour, corn starch, oat flour, rye flour, rice flour, potato flour, sweet potato flour, buckwheat flour, and soybean flour, etc. The small granular food materials include rice grains, wheat grains, barley grains, corn kernels, oats, rye grains, buckwheat seeds, sugar, salt, and soybeans, etc.

[0003] Specifically, for example, in a factory-type food material powder supply system used in the mixer of a noodle-making machine for producing udon dough, wheat flour of a specified average particle size, also known as udon flour, is stored in a silo equivalent to a storage tank. In a single mixing operation, a predetermined amount of wheat flour is transported to a supply tank called a grain bin, hopper, or receiving tank, and at a specified time, the wheat flour temporarily stored in the supply tank is added to the chamber of the mixer.

[0004] In such factory-type food material supply systems, the temperature of materials changes due to the influence of external air temperature during storage in storage tanks. Therefore, the temperature of the materials before processing such as stirring, mixing, kneading, or grinding can become excessively high compared to the ideal temperature for processing, especially in summer. If processing cannot be carried out at the material temperature within the specified range, it will adversely affect the quality of the product; therefore, it is required to cool to the specified temperature before processing.

[0005] For example, if the heat medium is a gas, the cooler supplies gas at a specified temperature to the container to directly cool the food material powder inside. Alternatively, if the heat medium is a liquid, a jacket is provided to the container to circulate liquid at a specified temperature to indirectly cool the food material powder inside.

[0006] Fine food powders like wheat flour, with an average particle size of tens to hundreds of μm, have relatively low thermal conductivity. The equilibrium moisture content of wheat flour is approximately 13% by weight when the average temperature of the raw materials is 25°C and the humidity is 40%. This varies slightly depending on the bulk density. Specifically, measured values ​​for thermal conductivity are as follows: 0.0409 W / (m·K) for low-gluten flour, 0.461 W / (m·K) for medium-gluten flour, and 0.0383 W / (m·K) for high-gluten flour. Therefore, the thermal conductivity of fine powders is clearly relatively low.

[0007] Therefore, when using a cooler with a gas or liquid as the heat medium for temperature adjustment, the outer side of the food powder block stored in the container is cooled, while the cooling or heating of the inner side lags behind. As a result, especially when there is a large amount of food powder in the container, it takes longer for the food powder to uniformly reach the required temperature, so it is desirable to shorten the cooling time.

[0008] For example, Patent Documents 1 and 2 disclose a food material powder supply device that, in the early stage of a vacuuming period where the exhaust volume of a water-sealed vacuum pump is greater than that of an oil-driven rotary vacuum pump, a vacuum is applied to the supply tank using a water-sealed vacuum pump. In the later stage of this vacuuming period, where evacuation using the water-sealed vacuum pump has become difficult, a vacuum is applied to the supply tank using an oil-driven rotary vacuum pump, reducing the gas pressure in the supply tank to below a predetermined pressure that generates latent heat of vaporization, thereby cooling the food material powder in the supply tank to the desired temperature. The vacuum device uses a filter to draw gas from the supply tank. The purpose of the filter is to remove food material powder contained in the gas discharged from the supply tank through the vacuum device.

[0009] In the relationship between water temperature and saturated water vapor pressure, the initial pressure at which water begins to evaporate at this temperature is already determined. For example, when the temperature of wheat flour is 30°C, in order to obtain the cooling effect from the latent heat of vaporization accompanying the evaporation of the tens of percent of water contained in the wheat flour, the pressure must be reduced to below 4000 Pa (40 hPa). Furthermore, the water needs to continue evaporating within a range of 5°C to 25°C suitable for mixing wheat flour until the desired temperature is reached. Therefore, using an oil-cooled rotary vacuum pump, which can operate over a wide vacuum range from low to high vacuum, is more advantageous in the later stages of vacuuming.

[0010] The exhaust volume of a vacuum device at a specified pressure, which can be calculated using the exhaust velocity, can be determined by simple calculation, neglecting volumetric efficiency, using the ratio of atmospheric pressure to the pressure in the supply tank. For example, in the case of a vacuum device with an exhaust volume of 20 L / min at 1 atmosphere, an exhaust volume of 2 L / min is required when the pressure in the supply tank is 0.1 atmosphere. Although oil rotary vacuum pumps can exhaust a wide range of vacuum regions, their exhaust volume in the low vacuum region is not greater than that of water-sealed vacuum pumps. Therefore, by using a water-sealed vacuum pump, which has a higher exhaust volume in the low vacuum region than an oil rotary vacuum pump, in the early stages of evacuation, the initial time of evacuation can be shortened. Furthermore, while water-sealed vacuum pumps are effective, especially in the low vacuum region, the reduction from the medium vacuum region to the high vacuum region to obtain the cooling effect from the latent heat of vaporization is time-consuming or difficult to achieve.

[0011] Regarding filtration devices, for example, the vacuum stirring and drying apparatus in Patent Document 3 discloses the following: A container holding the material to be dried is connected to a vacuum pump via an exhaust pipe equipped with a post-filter. After the connection between the exhaust pipe and the vacuum pump is severed by the pressure difference before and after the post-filter or by a time relay, external air is introduced into the exhaust pipe to remove blockages in the post-filter. Furthermore, the vacuum stirring and drying apparatus in Patent Document 3 discloses the following: A vacuum pump is used to reduce the pressure in the container, thereby lowering the boiling point of the water contained in the material to be dried, thus promoting the drying of the material by a heater. The heater is a jacket installed in the container. The jacket allows heat to be transferred from the container wall to heat the material to be dried in the container.

[0012] [Existing technical documents]

[0013] [Patent Literature]

[0014] [Patent Document 1] Japanese Patent No. 6541863

[0015] [Patent Document 2] Japanese Patent No. 6817403

[0016] [Patent Document 3] Japanese Patent Publication No. 51-143276 Summary of the Invention

[0017] [The problem the invention aims to solve]

[0018] However, the food material powder supply devices in Patent Documents 1 and 2 have room for improvement. The filter media of the filtration device located between the supply tank and the vacuum device gradually becomes clogged due to capturing food material powder contained in the gas discharged from the supply tank. As the filter media gradually becomes clogged, the gas flow between the supply tank and the vacuum device also gradually deteriorates. When the filter media becomes clogged, the time required to reduce the pressure in the supply tank to the specified pressure becomes longer. When the filter media becomes clogged, the time required to cool the food material powder in the supply tank to the specified temperature also becomes longer.

[0019] The purpose of the vacuum stirring and drying apparatus in Patent Document 3 is to dry the object to be dried. The pressure inside the container is reduced to the pressure of the low-vacuum region during the drying process. When clearing blockages in the post-filter, external air is introduced after disconnecting the container from the vacuum pump, causing the pressure inside the container to rise. In some cases, the pressure inside the container may return to atmospheric pressure. The pressure inside the container can be reduced again, for example, from the pressure that has risen to atmospheric pressure, simply until it is reduced to the pressure of the low-vacuum region. Therefore, for example, a water-sealed vacuum pump can be used to quickly reduce the pressure.

[0020] However, in the structure of the vacuum stirring and drying apparatus in Patent Document 3, when it is necessary to reduce the pressure in the container from a medium vacuum region to a high vacuum region to obtain the cooling effect caused by the latent heat of vaporization of the food material powder, during the cooling process of the food material powder, the pressure in the container rises to atmospheric pressure every time the post-filter is cleared of blockage, and then is reduced from a medium vacuum region to a high vacuum region. This process repeats itself. Therefore, even if the blockage of the post-filter is cleared, it will conversely cause the time required for the food material powder in the container to cool to the specified temperature to be longer. The industry hopes to clear the blockage of the post-filter during the cooling process of the food material powder and suppress the rise in pressure when clearing the blockage of the post-filter, so as to maintain the pressure at which the latent heat of vaporization is generated or quickly restore it to the pressure at which the latent heat of vaporization is generated. In short, the time required for the food material powder to cool to the specified temperature should always be kept short.

[0021] In view of the aforementioned problems, the object of the present invention is to provide a cooling mechanism in a feeding device for food material powders such as wheat flour. This cooling mechanism uses a vacuum device to evacuate the feeding tank through a filter, thereby cooling the food material powder in the feeding tank by means of latent heat of vaporization. The feeding device eliminates clogging of the filter media in the filter and suppresses the pressure rise in the feeding tank when the clogging is cleared, thus maintaining or rapidly restoring the pressure at which latent heat of vaporization is generated. In short, the time required to cool the food material powder to a specified temperature is always kept shorter. In the detailed description of embodiments of the food material powder feeding device of the present invention, several advantages obtainable by the present invention are shown each time.

[0022] [Technical means to solve the problem]

[0023] The present invention provides a food material powder supply device, comprising: a supply tank including an exhaust port for discharging internal gas, for supplying food material powder temporarily stored therein to a processing container of a food processing machine; a vacuum device including a water-sealed vacuum pump and an oil rotary vacuum pump, selectively using the water-sealed vacuum pump and the oil rotary vacuum pump to evacuate gas from the supply tank through the exhaust port, thereby creating a vacuum in the supply tank; a filter device including filter media and having an inlet and an outlet, the inlet introducing gas from the supply tank into the filter media, and the outlet outlet discharging gas introduced from the supply tank through the filter media from the inlet into at least the oil rotary vacuum pump of the vacuum device; and a gas supply device supplying external gas to the filter media from the outlet outlet. Gas; and a control device that operates the water-sealed vacuum pump in the early stage of a vacuuming period where the exhaust volume of the water-sealed vacuum pump per unit time is greater than that of the oil rotary vacuum pump, switches to the oil rotary vacuum pump in the later stage of the vacuuming period when the pressure has been reduced to the point where exhaust by the water-sealed vacuum pump becomes difficult, and operates the gas supply device at a predetermined time in the later stage of the vacuuming period, supplying the filter media with external gas from a position as close as possible to the outlet of the filter device during the process of evacuating the supply tank using the oil rotary vacuum pump, and removing the food material powder adhering to the filter media into the supply tank by means of the external gas expanding due to the pressure difference with the space being evacuated.

[0024] [The effects of the invention]

[0025] The food material powder supply device of the present invention continuously evacuates and minimizes the amount of gas supplied to the outside of the filter material of the filtration device, thereby eliminating the blockage of the filter material of the filtration device and minimizing the rise of the gas pressure in the supply tank at this time. It can maintain the gas pressure that generates latent heat of vaporization or quickly restore it to the gas pressure that generates latent heat of vaporization. In short, it can keep the time required to cool the food material powder to the specified temperature in a shorter time. Attached Figure Description

[0026] Figure 1 This is a schematic block diagram illustrating the overall structure of a factory-type wheat flour supply system, which includes the food material powder supply device of the present invention.

[0027] Figure 2 This is a front view of the food material powder supply device of the present invention.

[0028] Figure 3 This is a top view schematic diagram of the food material powder supply device of the present invention.

[0029] Figure 4 This is a front view showing the interior of the food material powder supply device of the present invention.

[0030] Figure 5 This is a top view schematic diagram showing the interior of the food material powder supply device of the present invention.

[0031] Figure 6 A schematic diagram showing the gas supply device.

[0032] Figure 7 for Figure 6 AA-direction view.

[0033] Figure 8 for Figure 6 BB-direction cross-section view.

[0034] Figure 9 for Figure 6 CC-direction cross-section view.

[0035] Figure 10 This is a flowchart illustrating an example of the control process in the food material powder supply device of the present invention.

[0036] Figure 11 A graph showing the relationship between water temperature and saturated water vapor pressure.

[0037] Explanation of symbols

[0038] 1: Food material powder supply device

[0039] 2: Food processing machinery (vacuum mixer)

[0040] 3: Storage tanks (silos)

[0041] 4: Intermediate storage tank (for wheat flour)

[0042] 5: Measuring device (scale)

[0043] 6: Foreign matter removal device (inline screen)

[0044] 7: Transfer device

[0045] 7a: Blower

[0046] 7b: Blower

[0047] 8: Control device

[0048] 10: Supply trough (grain container)

[0049] 11: Temperature detection device (temperature sensor)

[0050] 12: Vacuum device

[0051] 13: Filtration device

[0052] 13a: Inlet

[0053] 13b: Outlet port

[0054] 130: Filter media

[0055] 14: Gas supply device

[0056] 14a: Gas supply source (air compressor, blower)

[0057] 14b: Vacuum shut-off valve (fourth valve)

[0058] 15a: Vacuum shut-off valve (first valve)

[0059] 15b: Vacuum shut-off valve (second valve)

[0060] 15c: Vacuum shut-off valve (third valve)

[0061] 15d: Vacuum shut-off valve (seventh valve)

[0062] 16: Pressure detection device (barometric pressure sensor)

[0063] 17: Stirring shaft

[0064] 17a: Stirring blade

[0065] 17b: Stirring shaft rotation drive device

[0066] 20: Processing container (chamber)

[0067] 21: Stirring shaft

[0068] 21a: Stirring blade

[0069] 100: Tank

[0070] 100a: Exhaust port

[0071] 100b: Powder supply port

[0072] 100c: Powder discharge port

[0073] 100d: Inspection door

[0074] 100e: Vibration-applying component

[0075] 101: Connecting components

[0076] 121: Water-sealed vacuum pump

[0077] 121a: Vacuum shut-off valve (fifth valve)

[0078] 122: Oil rotary vacuum pump

[0079] 122a: Vacuum shut-off valve (sixth valve)

[0080] 123: Moisture removal device (cold trap)

[0081] 123a: Cooling water tank

[0082] 123b: Pump

[0083] 130: Filter media (filter screen)

[0084] 140: Air supply pipe

[0085] 140a: Air inlet

[0086] 141: First air supply pipe

[0087] 141a: First air inlet

[0088] 142: Second air supply pipe

[0089] 142a: Second air inlet Detailed Implementation

[0090] The following uses Figures 1 to 11 The following description illustrates one embodiment of the food material powder supply device of the present invention. Figure 1 This is a schematic block diagram illustrating the overall structure of a factory-type wheat flour supply system, which includes the food material powder supply device of the present invention. Figure 2 This is a front view of the food material powder supply device of the present invention. Figure 3This is a top view schematic diagram of the food material powder supply device of the present invention. Figure 4 This is a front view showing the interior of the food material powder supply device of the present invention. Figure 5 This is a top view schematic diagram showing the interior of the food material powder supply device of the present invention. Figure 6 A schematic diagram showing the gas supply device. Figure 7 for Figure 6 AA-direction view. Figure 8 for Figure 6 BB-direction cross-section view. Figure 9 for Figure 6 CC-direction cross-section view. Figure 10 This is a flowchart illustrating an example of the control process in the food material powder supply device of the present invention. Figure 11 This is a graph showing the relationship between water temperature and saturated water vapor pressure. Furthermore, Figure 1 The diagram is used to schematically represent the overall outline of a factory-type wheat flour supply system including the food material powder supply device of the present invention. Therefore, the relative size relationships between the multiple devices may sometimes differ from the actual product.

[0091] The food material powder supply device 1 of the embodiment is, for example, like... Figure 1 A factory-type wheat flour supply system, as shown, is equipped in the processing container 20 of the food processing machinery 2 to supply wheat flour as a food material powder.

[0092] First, use Figure 1 A factory-type wheat flour supply system will be described. The factory-type wheat flour supply system includes a food material powder supply device 1 according to the present invention. Furthermore, the factory-type wheat flour supply system includes a storage tank 3, an intermediate storage tank 4, a metering device 5, a foreign matter removal device 6, and a transfer device 7. The storage tank 3 is, for example, a silo 3. The intermediate storage tank 4 is, for example, a flour-use bin 4. The metering device 5 is, for example, a scale 5. The foreign matter removal device 6 is, for example, a linear sieve 6. The transfer device 7 is, for example, blowers 7a and 7b.

[0093] Wheat flour stored in silo 3 is conveyed by blower 7a, which acts as an air conveyor, to use box 4, which acts as a storage tank. The wheat flour conveyed to use box 4 is weighed to a predetermined degree by scale 5. The weighed wheat flour is then conveyed by blower 7b, which acts as an air conveyor, to inline sieve 6. Inline sieve 6 continuously spreads the incoming wheat flour onto a vibrating screen to remove foreign matter, and then conveys the wheat flour with foreign matter removed to food material powder supply device 1. The incoming wheat flour is temporarily cooled and stored in food material powder supply device 1, and then supplied to processing container 20 of food processing machinery 2 at a predetermined time.

[0094] Food processing machinery 2 is, for example, a vacuum mixer 2. Vacuum mixer 2 is, for example, a device used in a dough maker, confectionery maker, or bread maker to knead wheat flour, a raw material, to form a dough. Vacuum mixer 2 includes at least a chamber 20 and a mixing shaft 21. Chamber 20 corresponds to the processing container 20 of food processing machinery 2. Mixing shaft 21 includes mixing blades 21a that rotate within chamber 20 to knead the wheat flour.

[0095] Additionally, the vacuum stirrer 2 includes a vacuum device (not shown) and a filter device (not shown). In this case, the processing container 20 of the vacuum stirrer 2 is a chamber 20 equivalent to a vacuum container. The vacuum device is, for example, a vacuum pump. The vacuum pump evacuates the chamber 20 in such a way that the gas pressure becomes a low-vacuum region suitable for mixing wheat flour. The vacuum pump is, for example, a water-sealed vacuum pump. The filter device includes, for example, filter media. The filter media is, for example, a filter screen. When evacuating the chamber 20, the filter device removes wheat flour contained in the gas drawn by the vacuum pump. A vacuum shut-off valve (not shown) is installed between the vacuum pump and the filter device to open and close the connection between them. The vacuum shut-off valve is, for example, a valve. The valve opens when evacuating the chamber 20. Furthermore, the vacuum stirrer 2 may also be equipped with a moisture removal device (not shown) between the vacuum pump and the valve. The moisture removal device is, for example, a cold trap.

[0096] The food powder supply device 1 includes at least a supply tank 10, a vacuum device 12, a filter device 13, a gas supply device 14, and a control device 8. Additionally, the food powder supply device 1 includes a temperature detection device 11 and a pressure detection device 16. Furthermore, the food powder supply device 1 includes a moisture removal device 123. The cooling mechanism is comprised at least of the vacuum device 12 and the moisture removal device 123. The control device 8 controls at least the food powder supply device 1. Alternatively, the control device 8 can be configured to control the entire factory-type wheat flour supply system.

[0097] The supply tank 10 includes an exhaust port 100a for discharging internal gases and supplies food material powder temporarily stored inside to the processing container 20 of the food processing machinery 2. The supply tank 10 is, for example, a grain container 10.

[0098] The grain container 10 includes a tank 100, which temporarily stores a predetermined amount of wheat flour fed from the scale 5 through the inline sieve 6. The tank 100 is also a vacuum container evacuated by a vacuum device 12. The upper and middle portions of the tank 100 are cylindrical, while the lower portion is funnel-shaped. The term "funnel-shaped" refers to a shape where the inner diameter gradually decreases from top to bottom. The cylindrical and funnel-shaped portions are perpendicularly aligned with their axes, and these axes are coaxial.

[0099] The tank body 100 has an exhaust port 100a, a powder supply port 100b, and a powder discharge port 100c. The exhaust port 100a is, for example, like... Figures 1 to 5 As shown, it is located above the food material powder temporarily stored in the tank 100, and is on the side wall of the tank 100. The powder supply port 100b is, for example, like... Figures 1 to 3 As shown, it is located on the upper surface of the tank 100. The powder outlet 100c is like... Figure 1 , Figure 2 as well as Figure 4 It is opened on the lower surface of the tank 100 as shown.

[0100] The exhaust port 100a is connected to the vacuum device 12, and the gas in the tank 100 is discharged when the vacuum device 12 evacuates the tank 100. Figures 1 to 9 In the illustrated embodiment, the exhaust port 100a opens into the internal space of the connecting member 101, which is mounted on the outer wall of the tank 100. The connecting member 101 is also a vacuum container. By connecting the connecting member 101 to the vacuum device 12, the vacuum device 12 is connected to the exhaust port 100a. At least one exhaust port 100a is formed.

[0101] The powder supply port 100b is connected to the scale 5 via the inline sieve 6, supplying a predetermined amount of wheat flour from the scale 5 into the tank 100. For example, if the powder supply port 100b is positioned below the inline sieve 6, the predetermined amount of wheat flour measured by the scale 5 will have foreign matter removed in the inline sieve 6, and then will be supplied to the tank 100 from the inline sieve 6 through the powder supply port 100b by free fall.

[0102] The powder outlet 100c is connected to the chamber 20 of the vacuum mixer 2, discharging a specified amount of wheat flour from the tank 100 into the chamber 20. If it is like... Figure 1 In the embodiment shown, where the powder outlet 100c is positioned above the chamber 20 of the vacuum mixer 2, a predetermined amount of wheat flour in the tank 100 is discharged into the chamber 20 of the vacuum mixer 2 through the powder outlet 100c by free fall.

[0103] The grain container 10 includes multiple vacuum shut-off valves 15a, 15b, 15c, and 15d. Each vacuum shut-off valve 15a, 15b, 15c, and 15d is connected to the control device 8, and the control device 8 controls its opening and closing actions respectively.

[0104] The vacuum shut-off valve 15a, for example, is a first valve 15a, located between the exhaust port 100a and the vacuum device 12. The first valve 15a opens and closes the connection between the exhaust port 100a and the vacuum device 12. Here, when the connecting member 101 is provided, the first valve 15a is located between the connecting member 101 and the vacuum device 12 to open and close the connection between them.

[0105] The vacuum shut-off valve 15b, for example a second valve 15b, is located between the powder supply port 100b and the inline sieve 6. The second valve 15b opens and closes the connection between the powder supply port 100b and the inline sieve 6.

[0106] The vacuum shut-off valve 15c, for example a third valve 15c, is installed between the powder outlet 100c and the chamber 20 of the vacuum stirrer 2. The third valve 15c opens and closes the connection between the powder outlet 100c and the chamber 20 of the vacuum stirrer 2.

[0107] A vacuum shut-off valve 15d, for example a seventh valve 15d, is used to open the exhaust port 100a to the outside of the tank 100 when the air pressure in the tank 100 is set to atmospheric pressure. The seventh valve 15d opens and closes the communication between the exhaust port 100a and the outside of the tank 100. Here, when the connecting member 101 is provided, the seventh valve 15d is provided between the connecting member 101 and the outside of the tank 100 to open and close the communication between them.

[0108] When vacuuming the tank 100 using vacuum device 12, open the first valve 15a and close the second valve 15b, third valve 15c, and seventh valve 15d. When supplying wheat flour to the tank 100, open the second valve 15b and seventh valve 15d, and close the first valve 15a and third valve 15c. When discharging wheat flour from the tank 100, open the third valve 15c and seventh valve 15d, and close the first valve 15a and second valve 15b.

[0109] like Figures 1 to 5 As shown, the grain container 10 may include a stirring shaft 17 that rotates within the tank 100. The stirring shaft 17 includes stirring blades 17a and a stirring shaft rotation drive device 17b. The stirring shaft rotation drive device 17b causes the stirring shaft 17 to rotate, thereby stirring the wheat flour in the tank 100 by the stirring blades 17a.

[0110] The grain container 10 may also include an access door 100d to allow for maintenance of the container 100. Additionally, the grain container 10 may include a vibration application member 100e, which removes wheat flour adhering to the inner circumferential surface of the container 100 by applying vibration from the outer circumferential surface of the container 100. Furthermore, the grain container 10 may include an access window (not shown) for observing the contents of the container 100 from the outside. Additionally, the grain container 10 may include a lighting fixture that illuminates the contents of the container 100 when observed through the access window.

[0111] Pressure detection device 16 detects the air pressure in supply tank 10. Pressure detection device 16 is connected to control device 8 and outputs a signal indicating the detected air pressure in tank 100 to control device 8. Pressure detection device 16 is, for example, a pressure sensor 16. Pressure sensor 16 can be, for example, like... Figure 1 It is installed on the upper part of the tank 100 of the grain container 10 as shown. In addition, the pressure sensor 16 can also be installed in the required location as needed, so as to detect not only the pressure in the grain container 10, but also the pressure in the flow path between the exhaust port 100a and the filter device 13, or the pressure in the flow path between the vacuum device 12 and the filter device 13, etc.

[0112] Temperature detection device 11 detects the temperature of the food powder in the supply tank 10. Temperature detection device 11 detects the temperature of the food powder in the supply tank 10 at predetermined sampling times. Temperature detection device 11 is connected to control device 8 and outputs a signal indicating the detected temperature of the wheat flour to control device 8. Temperature detection device 11 is, for example, a temperature sensor 11. Figure 1 As shown, at least one temperature sensor 11 is installed on the tank 100 of the grain container 10 to detect the temperature of the wheat flour in the tank 100. Figure 1 , Figure 2 as well as Figure 4 In the embodiment shown, multiple temperature sensors 11 are installed at different positions along the height of the tank 100.

[0113] Vacuum device 12 includes a water-sealed vacuum pump 121 and an oil-filled rotary vacuum pump 122, and selectively uses both to evacuate gas from the supply tank 10 through exhaust port 100a, thereby creating a vacuum in the supply tank 10. At this time, vacuum device 12 reduces the gas pressure in the supply tank 10 to below a predetermined pressure that generates latent heat of vaporization, thereby cooling the food material powder in the supply tank 10 to a desired temperature. The desired temperature is suitable for processing the food material powder in the food processing machinery 2.

[0114] Figure 1The vacuum device 12 of the illustrated embodiment includes a water-sealed vacuum pump 121 and an oil-filled rotary vacuum pump 122, and selectively uses both to evacuate gas from the container 100 of the grain tank 10 through the exhaust port 100a, thereby creating a vacuum in the container 100. At this time, the vacuum device 12 reduces the pressure in the container 100 of the grain tank 10 to below a predetermined pressure that generates latent heat of vaporization, thereby cooling the wheat flour in the container 100 to the desired temperature. The desired temperature is suitable for kneading wheat flour in the vacuum mixer 2, for example, a temperature in the range of 5°C to 25°C.

[0115] Vacuum pumps are classified into several types, and their capabilities and limitations vary depending on the type. We know that it is difficult to establish a high vacuum within a vacuum container using only one type of vacuum pump, or it may take a considerable amount of time to achieve the desired high vacuum.

[0116] like Figure 11 As shown, the saturated water vapor pressure at a specified water temperature is known. For example, when the temperature of wheat flour is 30°C, to obtain a cooling effect from the latent heat of vaporization accompanying the evaporation of water contained in the wheat flour, the pressure must be reduced to approximately 4000 Pa (40 hPa), and the water must continue to evaporate within a range of 5°C to 25°C suitable for mixing wheat flour until the desired temperature is reached. Furthermore, for example, when the temperature of wheat flour is 30°C, to obtain a cooling effect from the latent heat of vaporization accompanying the evaporation of water contained in the wheat flour accumulated in the container 100 of the grain tank 10, the pressure must be reduced to between 1900 Pa (19 hPa) and 2300 Pa (23 hPa), and the water must continue to evaporate within a range of 5°C to 25°C suitable for mixing wheat flour until the desired temperature is reached. Furthermore, for example, when the temperature of wheat flour is 30°C, in order for the wheat flour accumulated in the container 100 of the grain storage tank 10 to obtain a cooling effect from the latent heat of vaporization accompanying the evaporation of the moisture contained in the wheat flour, the pressure must be reduced to between 1930 Pa (19.3 hPa) and 2230 Pa (22.3 hPa), and the moisture must be continuously evaporated within a range of 5°C to 25°C suitable for mixing wheat flour until the desired temperature is reached. Moreover, the pressure mentioned above is expressed as absolute pressure with absolute vacuum as zero. For example, if atmospheric pressure is set to 101.33 kPa, the pressure between 1930 Pa and 2230 Pa expressed as absolute pressure, when converted to gauge pressure with absolute atmospheric pressure as zero, is between -99.4 kPa and -99.1 kPa.

[0117] Therefore, to reduce the pressure to a level sufficient for cooling using a vacuum pump, it is advantageous to use an oil rotary vacuum pump 122, which has a wide operating range from low to high vacuum. If the exhaust gas contains a large amount of moisture, it will cause the oil rotary vacuum pump 122 to malfunction. A moisture removal device 123 is provided in the vacuum device 12 to remove moisture contained in the gas when the tank 100 of the grain container 10 is evacuated at least by the oil rotary vacuum pump 122. Additionally, if the exhaust gas contains a large amount of wheat flour, it will cause the oil rotary vacuum pump 122 to malfunction. A filter device 13, described later, is provided to remove particles such as wheat flour contained in the gas discharged from the tank 100 when the tank 100 of the grain container 10 is evacuated at least by the oil rotary vacuum pump 122.

[0118] At this point, the exhaust volume of the vacuum pump at a specified pressure, which can be calculated using the exhaust velocity, can be obtained by simple calculation, ignoring volumetric efficiency, using the ratio of atmospheric pressure to the pressure in the vacuum container. Therefore, for example, in the case of a vacuum pump with an exhaust volume of 20 L / min at 1 atmosphere, it has an exhaust volume of 2 L / min when the pressure in the vacuum container is 0.1 atmosphere.

[0119] Although the oil rotary vacuum pump 122 can exhaust a wide range of vacuum regions, its exhaust volume in the low vacuum region is less than that of the water-sealed vacuum pump 121. Therefore, in the vacuum device 12, the water-sealed vacuum pump 121 is operated in the early stage of the evacuation process until the pressure is reduced to the specified pressure. The oil rotary vacuum pump 122 is operated in the later stage of the evacuation process after the pressure is reduced to the specified pressure.

[0120] The water-sealed vacuum pump 121 is an effective vacuum pump, especially in the low vacuum region. However, reducing the vacuum from the medium vacuum region to the high vacuum region to obtain the cooling effect from the latent heat of vaporization is time-consuming or difficult to achieve. Nevertheless, the water-sealed vacuum pump 121 has a larger exhaust volume than the oil rotary vacuum pump 122 in the low vacuum region, so the decompression time can be shortened as long as it is in the low vacuum region.

[0121] When the water-sealed vacuum pump 121 is operated, to avoid reducing exhaust efficiency, the gas in the tank 100 of the grain container 10 can be evacuated via a bypass line without passing through the moisture removal device 123. Similarly, when the water-sealed vacuum pump 121 is operated, to avoid reducing exhaust efficiency, the gas in the tank 100 can be evacuated via a bypass line without passing through the filter device 13 described later. However, the filter device 13 can remove particles, including wheat flour, from the gas in the tank 100, thus purifying the exhaust from the water-sealed vacuum pump 121; therefore, it is preferable to pass the gas through the filter device 13.

[0122] The moisture removal device 123 is, for example, a cold trap 123. The cold trap 123 is cooled by circulating cooling water using a cooling water tank 123a and a pump 123b. The cooled cold trap 123 can remove moisture contained in the gas passing through it.

[0123] Figure 1 The vacuum device 12 of the illustrated embodiment includes a plurality of vacuum shut-off valves 121a and 122a. Each vacuum shut-off valve 121a and 122a is connected to a control device 8, and the control device 8 controls the opening and closing actions of each valve.

[0124] The vacuum shut-off valve 121a, for example, is a fifth valve 121a, located between the water-sealed vacuum pump 121 and the cold trap 123. The fifth valve 121a opens and closes the connection between the water-sealed vacuum pump 121 and the cold trap 123.

[0125] The vacuum shut-off valve 122a, for example, is a sixth valve 122a, located between the oil rotary vacuum pump 122 and the cold trap 123. The sixth valve 122a opens and closes the connection between the oil rotary vacuum pump 122 and the cold trap 123.

[0126] During the early stage of vacuuming when the exhaust volume of the water-sealed vacuum pump 121 per unit time is greater than that of the oil rotary vacuum pump 122, the vacuum device 12 opens the fifth valve 121a and closes the sixth valve 122a, thereby evacuating the grain tank 100 of the grain container 10 by the water-sealed vacuum pump 121. During the later stage of vacuuming when the pressure has been reduced to the point where exhaust by the water-sealed vacuum pump 121 becomes difficult, the vacuum device 12 closes the fifth valve 121a and opens the sixth valve 122a, thereby evacuating the grain tank 100 of the grain container 10 by the oil rotary vacuum pump 122. Furthermore, the fifth valve 121a and the sixth valve 122a can be replaced with a three-way switching valve. Furthermore, the switching structure using the fifth valve 121a and the sixth valve 122a can be replaced with a switching structure using a three-way switching valve.

[0127] The filtration device 13 includes filter media 130 and has an inlet 13a and an outlet 13b. The inlet 13a introduces gas from the supply tank 10 into the filter media 130, and the outlet 13b discharges the gas introduced from the supply tank 10 through the filter media 130 and the inlet 13a to at least the oil rotary vacuum pump 122 of the vacuum device 12. The filtration device 13 includes at least one filter media 130. The filter media 130 is a material or structure that allows gas to pass through but prevents particles such as wheat flour contained in the gas from passing through.

[0128] Figures 1 to 9The filtration device 13 of the illustrated embodiment includes a plurality of filter media 130. The filter media 130 is, for example, a filter screen 130. Each filter screen 130 is formed into a hollow cylindrical shape, with the hollow part open at one end and closed at the other end as a bottom surface.

[0129] Each filter screen 130 is installed in the tank 100 of the grain container 10. The opening of each filter screen 130 is connected to the exhaust port 100a of the tank 100. The inlet 13a of the filter device 13 is the outer surface 13a of each filter screen 130. At this time, the outer surface 13a of each filter screen 130 faces into the tank 100, allowing particles such as wheat flour contained in the gas in the tank 100 to adhere when a vacuum is drawn into the tank 100. In addition, the outlet 13b of the filter device 13 is the inner surface 13b of each filter screen 130. At this time, the internal space surrounded by the inner surface 13a of each filter screen 130 is connected to the internal space of the connecting member 101 described above. In addition, the outlet 13b is connected to the vacuum device 12 through the internal space of the connecting member 101. In this embodiment, the outlet 13b is connected to the water-sealed vacuum pump 121 and the oil rotary vacuum pump 122.

[0130] Furthermore, the shape and number of filter screens 130 are not limited to the embodiments described above. Alternatively, the filter device 13 may also be configured to include the connecting member 101 and the filter screen 130 described above, with the opening portion of the filter screen 130 directly connected to the connecting member 101 and the filter screen 130 inserted into the tank 100 from the exhaust port 100a of the tank 100.

[0131] The gas supply device 14 supplies external gas to the filter media 130 of the filter device 13 from the outlet 13b of the filter device 13. The gas supply device 14 is connected to the control device 8. The gas supply device 14 includes a gas supply source 14a and a gas delivery pipe 140, which allows external gas supplied from the gas supply source 14a to pass through, supplying the external gas to the filter media 130 from a position as close as possible to the outlet 13b of the filter device 13. At this time, the gas delivery pipe 140 is formed with a gas delivery port 140a for supplying external gas to the filter media 130.

[0132] As described below, the gas supply device 14 supplies external gas to the filter material 130 from the outlet 13b as close as possible to the filter device 13 during the process of evacuating the supply tank 10 using the oil rotary vacuum pump 122. The external gas expands due to the pressure difference with the space being evacuated, removing the food material powder adhering to the filter material 130 from the filter material 130 and allowing it to fall freely into the supply tank 10.

[0133] During the later stages of the vacuuming process, external gas is supplied at a predetermined time. While the external gas is being supplied, the tank 100 of the grain container 10 is being evacuated by the oil rotary vacuum pump 122. For example, the space as close as possible to the outlet 13b of the filter device 13 is also being evacuated by the oil rotary vacuum pump 122. The pressure in the evacuated space must be reduced to approximately 4000 Pa (40 hPa) or less. In some cases, the pressure in the evacuated space must be reduced to between 1900 Pa (19 hPa) and 2300 Pa (23 hPa). Furthermore, in some cases, the pressure in the evacuated space must be reduced to between 1930 Pa (19.3 hPa) and 2230 Pa (22.3 hPa). Regarding the amount of external gas supplied, a small amount is sufficient because the external gas, supplied from the outlet 13b as close as possible to the filter device 13 as possible, expands rapidly due to the pressure difference, thus removing wheat flour adhering to the surface of the filter device 13 on the inlet 13a side of the filter device 13. The external gas is supplied during the process of evacuating using the oil rotary vacuum pump 122, and the supply amount is small, so it is quickly evacuated after expanding under the pressure difference to remove wheat flour.

[0134] Therefore, unlike the case where external gas is violently sprayed onto the filter material 130 to remove food material powder adhering to the filter material 130 by means of the force of the spray, the gas supply device 14 utilizes the fact that the volume of external gas expands rapidly under a pressure difference, as described above, so that the amount of external gas supplied can be minimized. Furthermore, if the amount of external gas supplied is small, the pressure rise in the supply tank 10 can be suppressed as much as possible, thereby quickly restoring the pressure to the level at which the food material powder in the supply tank 10 generates latent heat of vaporization, or maintaining the pressure at which the food material powder in the supply tank 10 generates latent heat of vaporization. For example, the position of being as close as possible to the outlet 13b of the filter device 13 is such that even if the supply of external gas is such that the pressure in the supply tank 10, which is temporarily increased due to the supply of gas during vacuuming, can be quickly restored to the pressure at which the food material powder generates the latent heat of vaporization, or the supply of gas at which the pressure in the supply tank 10, which is temporarily increased due to the same reason, can be maintained, the food material powder attached to the filter material 130 can be removed by the expansion of the volume of the supplied external gas under the pressure difference.

[0135] When a plurality of exhaust ports 100a are formed on the supply tank 10, and the filter device 13 includes a plurality of filter media 130, with each filter media 130 respectively installed at each exhaust port 100a, the gas supply device 14 preferably includes a plurality of air supply pipes 140. Similarly, when a plurality of exhaust ports 100a are formed on the supply tank 10, and the filter device 13 includes a plurality of filter media 130, with each filter media 130 respectively installed at each exhaust port 100a, the gas supply device 14 preferably has a plurality of air supply ports 140a formed on the air supply pipes 140. Similarly, when a plurality of exhaust ports 100a are formed on the supply tank 10, and the filter device 13 includes a plurality of filter media 130, with each filter media 130 respectively installed at each exhaust port 100a, the gas supply device 14 preferably includes a plurality of air supply pipes 140 and has a plurality of air supply ports 140a formed on each of the air supply pipes 140.

[0136] Figures 1 to 9 The gas supply device 14 of the illustrated embodiment includes a gas supply source 14a, a first gas delivery pipe 141, and a second gas delivery pipe 142. The gas supply source 14a is, for example, an air compressor supplying compressed air, an air blower, or a gas cylinder storing compressed air. The external gas is, for example, clean air at atmospheric pressure or higher. The first gas delivery pipe 141 and the second gas delivery pipe 142 are installed in the connecting member 101 facing the filter screen 130.

[0137] The first gas supply pipe 141 is connected to the gas supply source 14a at one end and closed at the other end. Similarly, the second gas supply pipe 142 is connected to the gas supply source 14a at one end and closed at the other end. In this embodiment, the first gas supply pipe 141 is shorter than the second gas supply pipe 142. The first gas supply pipe 141 is positioned above the second gas supply pipe 142.

[0138] Figures 2 to 9 The filtration device 13 of the illustrated embodiment has six filter screens 130 arranged from one end of the first air supply pipe 141 and the second air supply pipe 142 to the other end. The three filter screens at one end, as mentioned above, are supplied with gas from the outside via the first air supply pipe 141. A first air inlet 141a is formed on the first air supply pipe 141 at a position facing the filter screen 130 supplied with gas via the first air supply pipe 141. The three filter screens at the other end, as mentioned above, are supplied with gas from the outside via the second air supply pipe 142. A second air inlet 142a is formed on the second air supply pipe 142 at a position facing the filter screen 130 supplied with gas via the second air supply pipe 142. By dividing the air supply pipe 140 into a first air supply pipe 141 and a second air supply pipe 142, the amount of gas supplied to each filter screen 130 can be made as equal as possible.

[0139] The gas supply device 14 is configured to supply external gas to the filter screen 130 from a position as close as possible to the outlet 13b of the filter device 13 through the first air inlet 141a and the second air inlet 142a.

[0140] Figures 1 to 9 The gas supply device 14 of the illustrated embodiment includes a vacuum shut-off valve 14b. The vacuum shut-off valve 14b is connected to a control device 8 and its opening and closing are controlled by the control device 8. The vacuum shut-off valve 14b, located between the gas supply source 14a and the gas delivery pipes 140 (first gas delivery pipe 141 and second gas delivery pipe 142), is, for example, a fourth valve 14b. The fourth valve 14b opens and closes the connection between the gas supply source 14a and the gas delivery pipes 140. The fourth valve 14b opens when the gas supply device 14 supplies external gas to the filter screen 130 from a position as close as possible to the outlet 13b of the filter device 13, and closes at other times.

[0141] The control device 8 is controlled in the following manner: during the later stage of the vacuuming process, the gas supply device 14 is operated at a specified time. While the oil rotary vacuum pump 122 is evacuating the supply tank 10, external gas is supplied to the filter material 130 from the outlet 13b as close as possible to the filter device 13. The food material powder attached to the filter material 130 is removed into the supply tank 10 by the external gas expanding due to the pressure difference with the space being evacuated.

[0142] Regarding the specified time mentioned above, for example, it is when the temperature of the food material powder in the supply tank 10, detected by the temperature detection device 11, gradually decreases according to a specified temperature gradient during the later stage of the vacuuming process. The control device 8 controls the process as follows: when the temperature of the food material powder in the supply tank 10, detected by the temperature detection device 11, gradually decreases according to a specified temperature gradient during the later stage of the vacuuming process, the gas supply device 14 is operated. During the process of evacuating the supply tank 10 using the oil rotary vacuum pump 122, external gas is supplied to the filter material 130 from a position as close as possible to the outlet 13b of the filter device 13. The external gas, which expands due to the pressure difference with the space being evacuated, removes the food material powder that has accumulated on the filter material 130 and is above a specified amount into the supply tank 10. At this time, the temperature detection device 11 detects the temperature of the food material powder in the supply tank 10 at each specified sampling time and outputs the temperature to the control device 8 in sequence.

[0143] The term "each sampling time" is, for example, "every second". The term "when the temperature of the food material powder in the later stage of the vacuuming process gradually decreases according to the specified temperature gradient" refers to the point when a specified amount of food material powder adheres to the filter material 130 of the filter device 13, and the vacuuming capacity of the supply tank cannot be achieved as intended when the oil rotary vacuum pump 122 evacuates the vacuum tank.

[0144] For example, the control device 8 may determine the latest temperature decrease between the latest detection temperature and the detection temperature a specified time ago or a specified number of detections ago during the later stage of the vacuuming period. When the latest temperature decrease is less than the specified temperature decrease for a specified number of consecutive specified numbers of times, it is determined that the temperature of the food material powder in the supply tank 10 decreases slowly in proportion to the specified temperature gradient.

[0145] The term "temperature measured a specified time ago" refers to the temperature measured ten seconds ago compared to the latest measured temperature. Similarly, the term "temperature measured a specified number of times" refers to the temperature measured ten times ago compared to the latest measured temperature. Regarding the specified temperature reduction amount, whenever it is determined that the temperature of the food material powder in the supply tank 10 is decreasing gradually in line with the specified temperature gradient, the specified temperature reduction amount can be appropriately set to be the same as the previous amount or different from the previous amount.

[0146] When multiple temperature sensors 11 are included, at least one temperature sensor 11 can be used for determination. Alternatively, when multiple temperature sensors 11 are included, the control device 8 can determine, for example, that the temperature of the food material powder in the supply tank 10 is decreasing slowly relative to a predetermined temperature gradient based on the determination result of any one of the multiple temperature sensors 11. Furthermore, when multiple temperature sensors 11 are included, the control device 8 can determine, for example, that the temperature of the food material powder in the supply tank 10 is decreasing slowly relative to a predetermined temperature gradient based on the determination results of at least two of the multiple temperature sensors 11. Additionally, when multiple temperature sensors 11 are included, the control device 8 can determine, for example, that the temperature of the food material powder in the supply tank 10 is decreasing slowly relative to a predetermined temperature gradient based on the determination results of each of the multiple temperature sensors 11.

[0147] The latest temperature decrease refers to how much the latest detected temperature has decreased since the temperature was detected a specified time ago or a specified number of times ago. For example, the latest temperature decrease is the value obtained by subtracting the latest detected temperature from the value of the temperature detected a specified time ago relative to the detection time point. Alternatively, the latest temperature decrease is the value obtained by subtracting the latest detected temperature from the value of the temperature detected a specified number of times ago relative to the detection time point. Regarding the latest temperature decrease calculated by subtraction as described above, a positive value is displayed if the temperature is decreasing; otherwise, a zero or negative value is displayed.

[0148] Alternatively, the specified time mentioned above could be, for example, when the pressure in the supply tank 10, detected by the pressure detection device 16, reaches the specified pressure during the later stages of the vacuuming process. Furthermore, the control device 8 can also control the process in the following manner: when the specified pressure is reached during the later stages of the vacuuming process, the gas supply device 14 is operated, and while the oil rotary vacuum pump 122 is evacuating the supply tank, external gas is supplied to the filter material 130 from a position as close as possible to the outlet 13b of the filter device 13. The external gas, expanding due to the pressure difference with the space being evacuated, removes the food material powder adhering to the filter material 130 and accumulating to a specified amount into the supply tank 10.

[0149] The control device 8 includes a storage device (not shown) for storing temperature data representing the detected temperature output from the temperature detection device 11. The storage device can store only the required temperature data by deleting temperature data older than a specified time each time the latest temperature data is stored. Additionally, the storage device stores the number of consecutive times the latest temperature decrease is less than a specified temperature decrease. Furthermore, the control device 8 preferably includes an input device (not shown) and a display device (not shown). The input device is, for example, a touch panel. The display device is, for example, an LCD monitor. An operator can input various settings into the control device 8 using, for example, an LCD monitor with a touch panel. The control device 8 stores the input settings into the storage device. Alternatively, the control device 8 may include an operation panel (not shown). The operation panel is used by the operator when manually operating the food powder supply device 1. Either the operation panel or the input device can also function as both.

[0150] Figures 1 to 9 The food material powder supply device 1 of the illustrated embodiment is controlled, for example, by a control device 8 in the following manner. The control device 8 is as follows: Figure 10The flowchart shown controls the food material powder supply device 1. Furthermore, the so-called air purging of the present invention shown in the description involves operating the gas supply device 14 while the tank 100 of the grain container 10 is being evacuated using the oil rotary vacuum pump 122. External gas is supplied to the filter screen 130 from a position as close as possible to the outlet 13b of the filter device 13. The wheat flour adhering to the filter screen 130 is removed by means of the external gas expanding due to the pressure difference with the space being evacuated.

[0151] First, the grain container 100 temporarily stores a predetermined amount of wheat flour. At this time, the first valve 15a, the second valve 15b, the third valve 15c, the seventh valve 15d, the fifth valve 121a, the sixth valve 122a, and the fourth valve 14b are all closed. Furthermore, the water-sealed vacuum pump 121 and the oil rotary vacuum pump 122 equipped in the vacuum device 12 can be pre-operated so that a vacuum can be quickly created in the container 100 when connected to it.

[0152] The control device 8 opens the first valve 15a and the fifth valve 121a, and uses the water-sealed vacuum pump 121 to evacuate the tank 100 (step S1). If the tank 100 is equipped with a stirring shaft 17, the rotation of the stirring shaft 17 is also started as needed. Furthermore, the period of evacuating the tank 100 using the water-sealed vacuum pump 121 is the early stage of the evacuation process.

[0153] The control device 8 determines whether the air pressure in the tank 100 has been reduced to a first air pressure that makes it difficult for the water-sealed vacuum pump 121 to exhaust air (step S2). The first air pressure can be preset.

[0154] When the air pressure in tank 100 has been reduced to the first air pressure, control device 8 opens the sixth valve 122a and closes the fifth valve 121a, and uses oil rotary vacuum pump 122 to evacuate tank 100 (step S3). At this time, the evacuation performed by water seal vacuum pump 121 stops due to the closure of the fifth valve 121a (step S4). Furthermore, the period of evacuation of tank 100 by oil rotary vacuum pump 122 is the later stage of the evacuation period.

[0155] The control device 8 determines whether the air pressure in the tank 100 has been reduced to the preset second air pressure (step S5).

[0156] When the air pressure in the tank 100 has been reduced to the second air pressure, the control device 8 opens the fourth valve 14b and performs the air purging of the present invention while the oil rotary vacuum pump 122 is evacuating the tank 100, removing the wheat flour attached to the filter screen 130 and allowing it to fall freely into the tank 100 (step S6).

[0157] The control device 8 repeats the following steps S8 to S10 until the temperature of the wheat flour in the tank 100 reaches the preset cooling temperature (step S7).

[0158] The control device 8 determines whether a preset time has elapsed (step S8).

[0159] After a predetermined time has elapsed, the control device 8 calculates the latest temperature decrease between the latest detected temperature and the detected temperature a predetermined time ago at each predetermined sampling time. When the latest temperature decrease is less than a predetermined temperature decrease for a predetermined number of consecutive predetermined number of times, it is determined that the temperature of the wheat flour in the tank 100 is decreasing gradually in line with a predetermined temperature gradient (step S9). Here, each predetermined sampling time is, for example, one second. The detected temperature a predetermined time ago compared to the latest detected temperature is, for example, the detected temperature ten seconds ago compared to the latest detected temperature.

[0160] When the control device 8 determines that the temperature of the wheat flour in the tank 100 is decreasing slowly in line with the specified temperature gradient, it opens the fourth valve 14b and performs the air purging of the present invention while the oil rotary vacuum pump 122 is evacuating the tank 100, thereby removing the wheat flour that has accumulated to a specified amount on the filter screen 130 and allowing it to fall freely into the tank 100 (step S10).

[0161] When the temperature of the wheat flour in the tank 100 reaches the preset cooling temperature, the control device 8 closes the first valve 15a and the sixth valve 122a, stops the vacuum pump 122 from performing vacuuming, and ends the cooling process of the wheat flour by the vacuum device 12 (step S11).

[0162] If the stirring shaft 17 is still rotating after the cooling process is completed, stop rotating the stirring shaft 17. Additionally, open the seventh valve 15d, which acts as an atmospheric vent valve, to return the air pressure in the tank 100 to atmospheric pressure. At a predetermined time, open the third valve 15c to discharge a predetermined amount of wheat flour from the tank 100 into the chamber 20 of the vacuum stirrer 2. Furthermore, the air purging of this invention can also be performed manually by an operator using a control panel at any time during or after the vacuuming process.

[0163] In the process of evacuating the supply tank 10 using a rotary vacuum pump 122, the food material powder supply device 1 of the present invention supplies external gas to the filter material 130 from a position as close as possible to the outlet 13b of the filter device 13 using a gas supply device 14. The external gas, expanding due to the pressure difference with the evacuated space, removes the food material powder adhering to the filter material 130, allowing it to fall freely into the supply tank 10. Therefore, the food material powder supply device 1 of the present invention minimizes the amount of external gas supplied to remove the food material powder adhering to the filter material 130, thereby minimizing the rise in gas pressure in the supply tank 10 due to external gas. Consequently, the gas pressure in the supply tank 10 can be quickly restored to the pressure required to generate the latent heat of vaporization of the food material powder, or the pressure required to generate the latent heat of vaporization of the food material powder can be maintained in the supply tank 10. In short, the time required to cool the food material powder to a predetermined cooling temperature can always be kept shorter.

[0164] This invention is not limited to the embodiments described above. Although several specific examples have been shown, the embodiments can be modified, components replaced, and combinations with known devices can be made without departing from the technical concept of this invention.

[0165] [Industry availability]

[0166] This invention can be applied to a feeding device for food material powders, including a feeding trough that supplies food material powders to the processing container of food processing machinery. This invention improves, for example, the operating efficiency of food processing machinery that processes food material powders, such as the mixers in noodle making machines, confectionery making machines, and bread making machines, and contributes to the development of food processing machinery.

Claims

1. A feeding device for food material powder, comprising: The supply tank includes an exhaust port for discharging internal gas, a powder supply port for supplying food material powder from the outside to the inside, and a powder discharge port for discharging the food material powder temporarily stored inside to the processing container of the food processing machinery. The first valve opens and closes the exhaust port; The second valve opens and closes the powder supply port; The third valve opens and closes the powder discharge port; A vacuum device, comprising a water-sealed vacuum pump and an oil rotary vacuum pump, and selectively using the water-sealed vacuum pump and the oil rotary vacuum pump, draws gas from the supply tank through the exhaust port, thereby creating a vacuum in the supply tank; A filtration device includes filter media disposed in the supply tank and has an inlet and an outlet. The inlet introduces gas from the supply tank into the filter media, and the outlet discharges gas from the supply tank introduced through the filter media from the inlet to at least an oil rotary vacuum pump of the vacuum device. A gas supply device that supplies external gas to the filter material from the outlet; and The control device operates the water-sealed vacuum pump in the early stage of a vacuuming period where its exhaust volume per unit time is greater than that of the oil rotary vacuum pump; switches to the oil rotary vacuum pump in the later stage of the vacuuming period when the pressure has been reduced to the point where exhaust by the water-sealed vacuum pump becomes difficult; and operates the gas supply device at a predetermined time in the later stage of the vacuuming period, supplying the filter media from a position as close as possible to the outlet of the filter device while the oil rotary vacuum pump is evacuating the supply tank. The external gas expands rapidly due to the pressure difference, and the expanding external gas, caused by the pressure difference with the evacuated space, removes the food material powder adhering to the filter material into the supply tank. This reduces the amount of external gas supplied so that it can quickly return to the pressure level necessary for the food material powder to generate its latent heat of vaporization, or maintain the pressure level necessary for the food material powder to generate its latent heat of vaporization, without violently spraying the external gas onto the filter material to remove the food material powder. The vacuum device reduces the gas pressure in the supply tank to below the specified gas pressure that generates the latent heat of vaporization. The position of the outlet as close as possible to the filter device is such that even if the external gas supply is sufficient to quickly restore the gas pressure in the supply tank, which temporarily rises due to the gas supply during the vacuuming process using the oil rotary vacuum pump, to the gas pressure required to generate the latent heat of vaporization of the food material powder, or to maintain the gas pressure required to generate the latent heat of vaporization of the food material powder even if the gas pressure in the supply tank temporarily rises for the same reason, the food material powder adhering to the filter material can be removed by the expansion of the supplied external gas volume under the pressure difference. The first valve, the second valve, and the third valve are vacuum shut-off valves. When evacuating the supply tank using the vacuum device, the first valve is opened, and the second valve and the third valve are closed.

2. The food material powder supply device according to claim 1, The system includes a temperature detection device that detects the temperature of the food material powder in the supply tank at predetermined sampling intervals. The specified time is when the temperature of the food material powder in the supply tank, detected by the temperature detection device, decreases gradually in proportion to a specified temperature gradient. The control device calculates the latest temperature decrease between the latest detection temperature and the detection temperature a specified time ago or a specified number of detections ago. When the latest temperature decrease is less than a specified temperature decrease for a specified number of consecutive specified numbers of times, it determines that the temperature of the food material powder in the supply tank decreases slowly in proportion to a specified temperature gradient.

3. The food material powder supply device according to claim 1, Includes a pressure detection device that detects the air pressure in the supply tank. The specified time is when the air pressure in the supply tank reaches the specified air pressure, as detected by the pressure detection device.

4. The food material powder feeding device according to any one of claims 1 to 3, wherein, The gas supply device includes a gas supply source and a gas delivery pipe. The gas delivery pipe allows external gas supplied from the gas supply source to pass through, supplying the external gas to the filter media from a position as close as possible to the outlet of the filter device. The air supply pipe is formed with an air inlet for supplying external gas to the filter material.

5. The food material powder supply device according to claim 4, wherein, When a plurality of exhaust ports are formed on the supply tank, the filter device includes a plurality of filter media, and each filter media is respectively installed on each of the exhaust ports, the gas supply device includes a plurality of gas delivery pipes.

6. The food material powder supply device according to claim 4, wherein, When a plurality of exhaust ports are formed on the supply tank, the filter device includes a plurality of filter media, and each filter media is respectively installed on each of the exhaust ports, a plurality of air supply ports are formed on the air supply pipe.

7. The food material powder supply device according to claim 4, wherein, When a plurality of exhaust ports are formed on the supply tank, the filter device includes a plurality of filter media, and each filter media is respectively installed on each of the exhaust ports, the gas supply device includes a plurality of gas delivery pipes, and each gas delivery pipe has a plurality of gas delivery ports formed on it.

8. The food material powder supply device according to claim 4, comprising: The fourth valve opens and closes the air inlet.

9. The food material powder supply device according to claim 8, wherein, The fourth valve is a vacuum shut-off valve.

10. The food material powder supply device according to claim 9, wherein, When supplying external gas using the gas supply device, the fourth valve is opened.

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