JP5691964B2 - Refrigerated display case - Google Patents

Description

  The present invention relates to a refrigerated display case capable of simultaneously displaying hot products and cold products.

  Conventionally, open / low-temperature open-type showcases (open showcases) that can be used for cooling / heating in supermarkets and convenience stores are cooled by fans around product display rooms with multiple product shelves installed. The product display room is divided into an upper hot room and a lower cold room, and the energization control of the heaters provided on the product shelf in the upper hot room is provided. The operation is switched between an all-cold operation in which the cooler is cooled and a cold-storage operation in which the hot chamber is heated and the cold chamber is cooled.

The following patent document is one of them, and as shown in FIGS. 5 and 6, the open showcase 1 is a cold / hot usable low temperature showcase installed in a store such as a supermarket, and has a cross section that opens to the front. The main body is composed of a substantially U-shaped heat insulating wall 3 and side plates 2 and 2 attached to both sides thereof, and the inner side of the heat insulating wall 3 is partitioned by a back panel 6 and a top panel 7 with a space between them. A cold air circulation duct 9 was formed between the panel 6, the top panel 7 and the heat insulating wall 3 from the back to the top.
JP 2006-3021 A

  A deck pan 10 extending forward is provided at the lower end of the back panel 6, and a product storage 11 is formed on the back side of the back panel 6, the top panel 7, and the deck pan 10. A lower duct 14 that communicates with the cold air circulation duct 9 and constitutes a part thereof is provided below the deck pan 10.

  The upper end of the cold air circulation duct 9 communicates with the upper cold air discharge port 16 located at the upper edge of the front opening of the product storage 11, and the front end of the lower duct 14 is the cold air suction port 17 located at the lower edge of the front opening of the product storage 11. Communicating with

  A blower 19 for supplying cold air is installed in the lower duct 14 below the deck pan 10, and a cooler 15 constituting a refrigeration cycle of the cooling device is installed in the cool air circulation duct 9 behind the product storage 11. It was installed vertically.

  A plurality of shelves 4, 4 </ b> A are installed in the product storage 11, and in the illustrated example, 6 levels are installed vertically. Each shelf 4 (from the top to the fifth step) except the bottom shelf 4A is provided with a pair of left and right brackets 21 and 21 having hook-like claws protruding rearward at the rear end, and the shelf plate 22 is attached to this bracket. The electric heater (not shown) for heating is attached to the lower surface of the shelf 22.

  Each shelf 4 can be engaged in the engagement holes of the shelf columns 23 attached to both front sides of the rear panel 6 in the product storage 11 so that the claws of the bracket 21 can be freely engaged and disengaged. Is installed so that the vertical position (height) can be changed.

  In the figure, reference numeral 24 denotes a cold air shielding plate, which is configured to protrude into the cold air circulation duct 9 so as to block the cold air circulation duct 9.

  First, when all the inside of the product storage 11 is to be cooled, the cool air shielding plate 24 does not block the cool air circulation duct 9, and when the blower 19 is operated in this state, The inside of the cold air circulation duct 9 rises and is discharged from the upper cold air discharge port 16.

  The discharged cool air cools the interior of the product storage 11 while forming a cool air curtain at the front opening of the product storage 11. Then, the circulation that is sucked into the lower duct 14 from the cold air suction port 17 and sucked into the blower 19 again is repeated. As a result, the entire area in the display chamber 11 is cooled to the refrigeration (or freezing) temperature, and the products on all the shelf boards 22 are cooled.

  Next, when using the upper part from the fourth shelf 4 from the upper side as a heating area and using the lower part as a cooling area for cooling, the cool air shielding plate 24 is moved to the rearmost side, The electric heaters on the shelves 4... At the second stage, the third stage from the top, and the fourth stage from the top are caused to generate heat.

  Since the cool air shielding plate 24 blocks the cool air upward from the communication portion, the cool air discharge from the upper cool air discharge port 16 is eliminated, and instead it is heated by the electric heater. The inside of the product storage 11 above 4 is a heating region.

  On the other hand, the cold air that has collided with the cold air shielding plate 24 bends forward, and the discharged cold air forms a cold air curtain in the front opening of the product storage 11 below the fourth shelf 4 while the fourth shelf. After being circulated and cooled in the product storage 11 below 4, the product is sucked from the cold air inlet 17. Thereby, the inside of the product storage below the fourth shelf 4 is a cooling region.

  Moreover, when making the whole goods storage 11 into a heating area | region, a cooling device and the air blower 19 are stopped, the electric heater of the shelf 4 of all the stages is heated, and the goods on the shelf board 22 are heated. Become. The lowermost shelf 4A is also composed of the same bracket 21 and shelf plate 22, but the shelf plate 22 is not heated or is separately heated by an electric heater.

  In such a cold storage warm type open showcase, when the entire product storage room is normally used as a cooling area, that is, cold air is discharged from the cold air discharge port at the upper edge of the opening, and the cold air curtain is spread over the entire opening of the product storage room. The capacity of the blower (fan size and motor output) is selected assuming that

  For this reason, when using cold / hot, the size of the front opening of the cool air curtain is reduced, the wind speed of the cool air curtain is not appropriate, and the entrainment of outside air increases too early, leading to the edges of the display interior walls and shelves. There was a problem of dew condensation on the parts.

  Patent Document 1 was proposed for the purpose of constructing an appropriate cool air curtain even when the cooling area was changed, and the rotation speed of the blower was adjusted according to the number of shelves heated by the heater. A control device is provided.

  With this control device, if the number of shelves heated by the heater is increased and the rotational speed of the blower is reduced, the air velocity of the cold air curtain is set to an appropriate value as the cooling area is reduced. It is possible to drop to

  The above-mentioned Patent Document 1 aims to more effectively realize condensation reduction and intrusion heat load reduction in the display room by controlling the wind speed of the cold air curtain. It cannot be said that adequately appropriate control can be realized only by reducing the rotational speed of the blower as the number of shelf stages to be heated increases.

  However, the product temperature of the heated beverage bottle in the upper hot chamber (warming area) during hot & call operation affects the ambient outside air temperature particularly in the cold showroom storage case of the open showcase model having the warming function. For example, when the ambient temperature is low, the beverage temperature tends to be low, and when the ambient temperature is high, it tends to be high.

  In addition, since the cool air cooled by the cooler is distributed to each chamber (cooling region) through the duct as described above, the airtightness of each chamber is sufficient even if each chamber is partitioned. It is difficult to ensure the temperature of the heater, and the cool air to the lower cold chamber may adversely affect the upper hot chamber, and the excess cool air hinders the heating of the heater additional heating shelf. This tendency is particularly strong when the ambient outside air temperature is low.

  The purpose of the present invention is to reduce the wind speed of the cool air curtain to an appropriate value with respect to the cooling area by reducing the rotational speed of the blower so as to eliminate the disadvantages of the conventional example and avoid unnecessary cooling. In addition to simply increasing the number of shelves heated by the heater, the appropriate heating corresponding to the ambient outside air temperature is performed. Alternatively, it is to provide a refrigerated display case in which cooling can be obtained.

In order to achieve the above object, the present invention according to claim 1 is characterized in that a ventilation path for circulating cold air through a cooler by a blower around a merchandise display room in which a plurality of merchandise shelves are installed in multiple stages, and a shelf for product display in which a plurality of stages erection, part of the shelf and the shelf warmed by the heater, of the display chamber from the front of the lowermost shelf of the pressurized Yutakatana by discharging cool air By forming a cold air curtain in the opening , a heating area heated by the heater is formed in the display room, and a cooling area is formed below the heating area, and further a temperature sensor and cooling measured by the temperature sensor In a refrigerated display case with a control device that changes the fan air flow rate in the cooling state when viewed from the shelf side in the area, the difference between the shelf temperature and the target when viewed from the shelf side in the heating area is If it is large, the stable state to the target temperature is If There is for summarized as reducing the air volume.

According to the first aspect of the present invention, it is detected that the shelf side in the cooling region is properly performing the cooling action, and the fan air volume in the cabinet is changed, for example, the number of rotations of the blower is decreased to reduce the cooling region. In contrast, it is possible to reduce the wind speed of the cold air curtain to an appropriate value, and in addition to the control from the HOT capability, the heaters on the shelves in the heating area can be turned on / off. It is controlled to turn off the heater when it reaches a certain temperature, for example, 6 or 70 degrees, and turn on the heater when it reaches, for example, it is judged that the HOT ability is strong or weak in the thermo operation time within 30 minutes. However, it is possible to control whether the cooling is prioritized if the temperature difference is detected based on the temperature difference whether the temperature is warm or not yet warmed.

The gist of the present invention described in claim 2 is to cancel the request for the heating area in order to prioritize the cooling area when the internal air flow rate mode is Hi when viewed from the shelf side in the cooling area. Is.

According to the present invention described in claim 2 , the priority between the control of claim 1 and the control of claim 3 is clarified. If the HOT capability is sufficient, the cooling method (COLD 9 is preferred) If it does not warm up, the ability of COLD can be given up and the amount of blown air can be reduced.

  As described above, the cooler / warm-up showcase of the present invention basically looks at the capability of the HOT, and if it is not possible, the rotational speed of the blower is reduced to reduce the cooling air curtain against the cooling area. It is possible to reduce the wind speed to an appropriate value, and the control at that time is not simply performed as the number of shelves heated by the heater increases, but the ambient outside air Appropriate heating or cooling corresponding to the temperature can be obtained.

  According to the present invention, the number of HOT shelves does not matter at all, and even if there are many or few HOT shelves, it is easy to cool, that is, when the outside air is high, the air volume of the blower When the outside air temperature is high and HOT is likely to be generated, the air volume of the blower is decreased, and when the outside air temperature is low and HOT is difficult to be generated, the HOT ratio is increased. Can do.

  That is, HOT, in other words, the fact that it is difficult to warm up means that it is easy to cool, so there is no practical problem even if the air volume of the blower is lowered, so HOT is given priority, the outside air temperature is high, and HOT is output. If it is easy, since it is actually warm, it is possible to control to give priority to COLD.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 to 3 are a longitudinal sectional side view, a front view, and a perspective view showing an embodiment of a cold storage warm showcase of the present invention, and the same components as those in FIGS. 5 and 6 showing the conventional example are the same. Reference numerals are attached.

  In the figure, reference numeral 1 denotes an open showcase as a cold / hot usable low temperature showcase installed in a store such as a supermarket, and the basic structure thereof is the same as in FIGS. 5 and 6 showing the conventional example.

  The open showcase 1 is composed of a heat insulating wall 3 having a substantially U-shaped cross section that opens to the front, and side plates 2 and 2 attached to both sides thereof, and a rear panel with a space between the inner sides of the heat insulating wall 3. 6 and partitioning by the top panel 7, a cold air circulation duct 9 was formed between the back panel 6, the top panel 7 and the heat insulating wall 3 from the back to the top.

  Further, a deck pan 10 extending forward is provided at the lower end of the back panel 6, and a product storage 11 is formed on the back inside the back panel 6, the top panel 7, and the deck pan 10. A lower duct 14 that communicates with the cold air circulation duct 9 and forms a part thereof is provided below the deck pan 10.

  The upper end of the cold air circulation duct 9 communicates with the upper cold air discharge port 16 located at the upper edge of the front opening of the product storage 11, and the front end of the lower duct 14 is the cold air inlet 17 located at the lower edge of the front opening of the product storage 11. Communicate with.

  Also, a blower 19 for supplying cold air is installed in the lower duct 14 below the deck pan 10, and a cooler 15 constituting a refrigeration cycle of a cooling device is installed in the cool air circulation duct 9 behind the product storage 11. Is installed vertically.

  A plurality of shelves 4, 4 </ b> A are installed in the commodity storage 11, and in the illustrated example, four tiers are installed vertically. Each shelf 4 (from the top to the third step) except the bottom shelf 4A is provided with a pair of left and right brackets 21 and 21 having hook-like claws protruding rearward at the rear end, and the shelf plate 22 is attached to this bracket. The electric heater (not shown) for heating is attached to the lower surface of the shelf 22.

  Each shelf 4 can be engaged in the engagement holes of the shelf columns 23 attached to both front sides of the rear panel 6 in the product storage 11 so that the claws of the bracket 21 can be freely engaged and disengaged. Is installed so that the vertical position (height) can be changed.

  In the figure, reference numeral 24 denotes a cold air shielding plate, which is configured to protrude into the cold air circulation duct 9 so as to block the cold air circulation duct 9. The cold air shielding plate 24 is slidably provided on each shelf 4, and a member that closes the inside of the cold air circulation duct 9 can be selected as necessary.

  In the machine room 8 formed in the lower part of the open showcase 1, a condenser 12 as a cooling unit, a condenser fan 13, a drain evaporator 18, electrical boxes 20a and 20b, an accumulator 26, a compressor 27 and the like are installed. To do. The drain evaporator 18 includes an evaporation plate, an evaporation dish, and an overflow tank.

  The electrical box 20a includes an earth leakage breaker, a digital thermometer / indicator, a hot / cold changeover switch, a cold storage shelf storage switch, and a refrigerator switch (cooling on / off).

  The machine room 11 is surrounded by a panel 29, and a slit 25 for taking in air is formed in the panel 29 on the front side or side of the showcase.

  In addition, although illustration is abbreviate | omitted, in the said electrical equipment box 20a or 20b, the control apparatus (microcomputer) which performs control of the electric heater for heating of the lower surface of the shelf 22 and control of the air blower 19 is provided.

  As an example of detecting the outside air temperature, for example, a temperature sensor 28 is attached to the inlet side of the condenser 12, and the detection output of this temperature sensor is also introduced into the control device (microcomputer). It was supposed to be controlled.

  First, when all the inside of the product storage 11 is to be cooled, the cool air shielding plate 24 does not block the cool air circulation duct 9, and when the blower 19 is operated in this state, the cooler 15 is heat-exchanged. The cold air rises in the cold air circulation duct 9 and is discharged from the upper cold air discharge port 16.

  The discharged cool air cools the interior of the product storage 11 while forming a cool air curtain at the front opening of the product storage 11. Then, the circulation that is sucked into the lower duct 14 from the cold air suction port 17 and sucked into the blower 19 again is repeated. As a result, the entire area in the display chamber 11 is cooled to the refrigeration (or freezing) temperature, and the products on all the shelf boards 22 are cooled.

  Moreover, when making the whole goods storage 11 into a heating area | region, a cooling device and the air blower 19 are stopped, the electric heater of all the shelves 4 and 4A is heated, and the goods on the shelf board 22 are heated. .

  Next, when any one of the first to third shelf 4 from the top is used for heating as a heating area and the bottom is used for cooling as a cooling area, the inside of the cold air circulation duct 9 is cooled by the cold air shielding plate 24. The electric heaters of the upper shelves 4 and 4A in the closed cold air circulation duct 9 are closed and heated.

  Since the cool air shielding plate 24 blocks the cool air upward from the communicating portion, the cool air discharge from the upper cool air discharge port 16 is eliminated, and instead it is heated by the electric heater. The inside becomes a heating region.

  On the other hand, the cold air that has collided with the cold air shielding plate 24 bends forward, and the discharged cold air is not heated by the electric heater while constituting a cold air curtain in the front opening of the lower product storage 11. After circulating through the storage 11 and cooling, it is sucked from the cold air inlet 17. Thereby, the inside of the lower product storage is a cooling region.

  In the present invention, as a first control, when viewed from the side of the shelves 4 and 4A that are not heated by the electric heater, the air volume of the blower 19 that is the internal fan from the cooling state is classified as, for example, Hi, Mid, and Lo from the high range. Select from the selected mode. And as a simple required cooling capacity, the ratio of the air volume is determined from the outside air temperature state.

  As a second control, when the difference between the shelf temperature and the target is large when viewed from the shelf 4 side in the heating region, or when the stable state to the target temperature is poor, the air flow rate of the blower 19 is lowered.

  However, when viewed from the shelf 4, 4A side of the cooling area (Cold), when the internal air flow rate mode of the blower 19 is Hi, the cooling area (Cold) is given priority, so the request for the heating area (HOT) is made. Cancel. In short, the air volume is suppressed in the HOT state while giving priority to cooling. When it gets cold, increase the allocation to HOT capacity and adjust the air volume.

To explain these three controls in more detail, FIG. 7 shows the control flow.
The determination of the internal fan air volume (rotational speed) is as follows: Calculation of cold state of internal temperature → 2. Calculation of cooling progress in the chamber → 3. From the cooling state and progress state of the internal temperature → 4. 4. Temporary determination of internal fan air volume based on internal fan air quality mode and outside air temperature. Set the rate of airflow suppression from the hot state of the HOT shelf → 6. Judgment on whether to give priority to cooling side, → 7. When priority is given, the procedure is to determine the internal fan air volume by the wind equation from the HOT shelf.

  The timing of control is changed by the number of rotations according to the control period of the internal fan (blower 19). In addition, when all are a heating area | region (ALLHOT), the internal fan (blower 19) shall be stopped.

Table 1 below shows control of the internal fan (blower 19) and calculation tables. 1 above. Judgment of how much the inside of the chamber is currently cooled is that the Saga between the inside temperature and the target temperature is not as cold as it is, and the temperature is cold when it is small. Therefore, the difference is Δtj and the inside temperature−target temperature = Δtj And
Then, ranking is performed according to the magnitude of the difference, and here, it is treated as ΔTevaj as a rank that is not so cold. The conversion table for this is shown in Table 1 below.

  2. In order to determine the original value of the internal air volume based on the cooling progress status and the current cooling status, the difference between the internal temperature and the target temperature Δtj is measured 3 minutes later, and the previous tj Divide the condition according to whether it is colder than -1.

  The internal fan air volume mode, which is the source of the internal air volume, is determined from the condition classification and the following Table 2 of Δtj. The idea is to increase the air flow if it is not cold, and to reduce the air flow if it is cold. The smaller the internal fan airflow mode here, the more airflow is required. Table 2 below shows the air volume mode of the internal fan (blower 19).

  3 above. In the internal fan wind good mode and the provisional determination of the air volume of the internal fan by the outside air, the idea is to increase the air volume as it cools. If the outside air is high, naturally it is necessary to increase the air volume in order to cool it. The reverse if the outside air is low. Therefore, if the rated air volume of the fan is set to 100% and cooling is low, the air volume is decreased. Table 3 below shows the internal fan reference air volume ratio.

  4. In the air volume suppression request from the HOT shelf, the following is performed when the HOT shelf is set. If the shelves are not warm, the air volume is reduced from the fan air volume obtained from the cold state, and it is urged to warm up. The shelf is stabilized around the target temperature by turning on and off the heater. In addition, when using an opportunity contact, on / off is performed at intervals of several minutes, and in order to suppress contact wear, the shelf temperature may be cold when off (during thermo operation). Further, when the thermo is frequently operated, it can be judged that it can be heated in terms of ability even if the current temperature is low. Therefore, in the case of whether the thermostat is currently operating or not, whether or not the temperature is lower than the shelf target temperature and the rate of lowering the internal fan air volume are determined from the map based on the map of the thermoactuation frequency.

  When there are a plurality of shelves, the difference between the HOT shelf and the target temperature is calculated for each shelf, and the value with the largest difference is selected. Table 4 below shows the internal fan reference air volume ratio as a result of the shelf HOT temperature heating capability determination.

  The control for heating the shelves 4 and 4A with the electric heater sets the number of stages, and the controller generates a function of energizing and heating the designated electric heaters of the shelves 4 and 4A.

  Each shelf has a temperature sensor (not shown) so that the shelves 4 and 4A heated by the electric heater do not exceed the target temperature, and the controller controls energization based on the temperature. The energization control is stopped or restored with a simple temperature threshold by a thermostat (stat).

The count of the number of thermo operation is as follows.
(1) The timer count is started after the HOT shelf heating stage number is set.
(2) The number of thermo-ONs of the HOT shelf at the boundary with COLD is counted for 0 to 10 hours and 30 minutes, and the condition for the number of thermo-operations is determined based on the number of counts.

  Also, the thermo state of the HOT shelf at the boundary with COLD is flagged. The flag is “1” when the thermo is ON, and the flag is “0” when the thermo is OFF.

When the HOT shelf at the boundary with COLD is thermo-ON, the air volume ratio subtraction rate is calculated under condition 1.
(3) When the thermo is OFF, the air volume ratio subtraction rate is calculated under the conditions 2 to 4 based on the difference between the HOT shelf temperature and the target temperature.
(4) At the time of defrosting, timer count reset & start, thermo count reset & start, and shift to (2).

Timer & thermo count reset when operation is stopped. At the start of operation, the timer & thermo-count starts and shifts to (2).
* At ALLCOLD and ALLHOT, timer count, thermocount reset & stop.
(5) If the HOT shelf heating stage number setting is changed, start from (1).

  The target shelf for such detection is a HOT shelf at the boundary with Cold as shown in FIG.

  5. above. In the air volume setting with cooling priority, immediately after the operation, if the shelf to be cooled is not cooled or the shelf to be warmed is not warmed, the cooling is higher as the capacity, so the cooling is done first. Then, warm it up. Therefore, the air volume is strong at first, and when it cools down, HOT is taken into consideration. Therefore, when it cools strongly, the air volume suppression request | requirement calculated | required by the 4th term is canceled. Calculation constants for this are obtained from the internal fan air volume mode.

6. above. The air volume is determined by putting the constants obtained so far into the following formula and determining the internal fan air volume. Therefore, said 5. If the calculation constant obtained in the air flow setting internal term in the cooling priority is 0, the value in parentheses is 1, and the above 4. The air volume suppression request obtained in the air volume suppression request term from the HOT shelf is zero.
Internal fan air volume = Internal fan standard rotation speed x Internal fan standard air flow rate x (1-Internal fan operation constant x Air flow rate subtraction ratio)

  Here, the internal fan reference rotation speed indicates the rotation speed of the fan motor determined for each product. In this calculation, when the outside air is low and the cooling is sufficient, the internal fan air volume is 30% of the reference rotational speed. On the other hand, if it is warmed well and the outside air is high, it will be 75%. The calculation of the internal fan is based on the constants shown in Table 5 below.

It is a vertical side view which shows one Embodiment of the cold storage showcase of this invention. It is a perspective view which shows one Embodiment of the cold storage showcase of this invention. It is a top view of the machine room which shows one Embodiment of the cold storage showcase of this invention. It is a table | surface which shows a detection object shelf. It is a vertical side view of a refrigerated display case. It is a perspective view of a refrigerated showcase. It is a flowchart of the air volume determination of this invention.

DESCRIPTION OF SYMBOLS 1 Open showcase 2 Side plate 3 Insulation wall 4, 4A Shelf 5 Shelf duct member 6 Back panel 7 Top panel 8 Machine room 9 Cold air circulation duct 10 Deck pan 11 Goods storage 12 Condenser 14 Lower duct 15 Cooler 16 Upper cold air discharge Outlet 17 Cold air inlet 18 Drain evaporator 19 Blower 20a, 20b Electrical box 21 Bracket 22 Shelf plate 23 Shelf column 24 Cold air shielding plate 25 Slit 26 Accumulator 27 Compressor 28 Temperature sensor 29 Panel

Claims (2)

Around a product display room in which a plurality of product shelves are installed in multiple stages, an air passage that circulates cool air through a cooler by a blower, and a product display shelf installed in a plurality of stages in the display room, some were the shelf is warmed by a heater, the by configuring the cooling air curtain at the opening of the display chamber by discharging cool air from the front of the lowermost shelf pressurized Yutakatana, the said display chamber A heating area heated by a heater and a cooling area below the heating area are further configured. In addition , the internal fan is in a cooling state as viewed from the shelf side in the cooling area measured by the temperature sensor and the temperature sensor. In a refrigerated display case equipped with a control device that changes the air volume, when the difference between the shelf temperature and the target is large when viewed from the shelf side in the heating area, if the stability to the target temperature is poor, the air flow rate cold warehouse, characterized in that the lower the Yokesu.
The refrigerated storage showcase according to claim 1, wherein when the internal air flow rate mode is Hi when viewed from the shelf side in the cooling region, the request for the heating region is canceled in order to prioritize the cooling region. .

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