JPH0119026Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to a show case equipped with a greenhouse for products.

(Prior Art) Conventionally, show cases as shown in FIGS. 4 to 8 are known. That is, 1 is a vertically long box-shaped show case main body, and the lower part of the show case main body 1 is a room 2 in which a cooling unit (not shown) is arranged.
A refrigerator compartment A is provided above the room 2 in which products are displayed and kept cool by the cooling unit.Furthermore, above the refrigerator compartment A, products are displayed and kept warm by the hot plate 3. A greenhouse B is provided. Further, a partition plate 4 is interposed between the refrigerator compartment A and the greenhouse compartment B, and a plurality of product shelves 5 are provided in the refrigerator compartment A,
In the greenhouse room B, there are provided a plurality of tiers of hot plates 3 on which products are placed. The surroundings of the cold and hot storage rooms A and B are made of glass, and a door 7 equipped with transparent glass 6 is provided in front of the opening of the cold and hot storage rooms A and B.
Note that 8 is a caster.

As shown in FIGS. 5 and 6, the hot plate 3 includes an upper plate 9, a plate heater 10,
It consists of a heat insulating member 11, a thermostat 12, a holding plate 13 for fixing the thermostat 12 to the plate heater 10, a fuse 14 attached to the holding plate 13, and a lower plate 15.

Furthermore, as shown in FIG. 7, the plate heater 10 covers the entire surface of the square aluminum foil 16.
It consists of heating wires 17a glued at predetermined intervals, lead wires 18 connected to one end and the other end of the heating wires 17a, respectively, and a temperature control section 19 provided approximately at the center of the aluminum foil 16. There is. The temperature control section 19 includes a fuse 14 and the thermostat 1.
2, and an electric circuit as shown in FIG. 8 connects the temperature control section 19, a commercial power source 20, the heating wire 17a, a power source changeover switch 21, and a lead wire 18 that connects these in sequence. It consists of Then, the power selector switch 21
The COM. terminal is connected to the power source 20, the NC terminal is connected to the heating wire 17a via the temperature control section 19, and the COM. terminal of the thermostat 12 is connected to the power source 20 via the power changeover switch 21.
Furthermore, the NC terminals are respectively connected to the heating wires 17a. And, the thermostat 1 is always
The COM. terminal and NC terminal of No. 2 are connected.

Further, the plate heater 10 is interposed between the upper plate 9 and the lower plate 15. Note that 14a is a screw for fixing the fuse 14 to the presser plate 13.

Therefore, when the COM. terminal and NC terminal of the power supply selector switch 21 are connected and the electric circuit is closed, the electricity from the power supply 20 passes through the fuse 14 and the COM. terminal and NC terminal of the thermostat 12. The power line 17a is energized. Thereafter, the heating wire 17a is heated and when the temperature rises to a predetermined temperature, the COM. terminal and the NC terminal of the thermostat 12 are separated and the electric circuit is opened. Therefore, the electricity supply to the heating wire 17a is cut off, and the temperature of the hot plate 3 decreases. Furthermore, when the temperature drops to a predetermined temperature, the thermostat 1 is turned on again.
The COM. terminal and the NC terminal of No. 2 are connected, the heating wire 17a is heated, and the temperature of the hot plate 3 is increased, so that the products in the greenhouse B are kept at a constant temperature.

(Problems to be Solved by the Invention) Since the area around the greenhouse chamber B of the conventional show case is formed of a plurality of glasses, especially at low temperatures, heat from the glass portion in the greenhouse chamber B is absorbed. A large amount is released to the outside through the glass portion. Therefore, products placed near the center of the greenhouse B, so-called near the center on the hot plate 3, are heated to a desired temperature, but the hot plate 3
Products placed on the upper periphery do not reach the desired temperature. Of course, the thermostat 12 is turned on so that the product on the periphery of the hot plate 3 reaches the desired temperature.
The temperature may be set higher, but in this case, the temperature of the product placed closer to the center of the hot plate 3 will be higher than the desired temperature. Therefore, there is a significant temperature difference between the center and the periphery of the hot plate 3, resulting in the problem that the product cannot be stored properly.

(Purpose of the invention) In view of the above-mentioned problems, the present invention attempts to provide a case that can maintain a uniform temperature throughout the greenhouse.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a show case equipped with a heater that generates heat by electric resistance and a hot plate 3 on which products are placed at the lower part of the greenhouse chamber B. A first heater 17b that is continuously energized is disposed at the periphery of the hot plate 3, and a second heater 17c that is intermittently energized near the center.When the temperature is higher than a predetermined temperature, the second heater 17c It has a control element 12 that opens the electrical circuit and performs the intermittent energization.

(Function) According to the present invention, the peripheral portion of the hot plate is continuously heated by the first heater, and the central portion of the hot plate is heated by the second heater whose electric circuit is opened and closed by the control element. Intermittent heating.

(Embodiment) An embodiment of the present invention will be described based on FIGS. 1 to 3, with the same reference numerals assigned to the same components as in the conventional example. That is, the substantially square plate heater 1
0 is an aluminum foil 16, a first heater, for example, a heating wire 17b, which is arranged at a predetermined interval on the periphery of the aluminum foil 16, and a first heater, for example, a heating wire 17b, which is arranged in a meandering manner at a predetermined interval near the center of the aluminum foil 16. A second heater provided, for example, a heating wire 17c, a temperature control unit 19 provided at the center of the plate heater 10, and a second heater connected to one end and the other end of the heating wire 17b and the heating wire 17c, respectively. It consists of a lead wire 18.

The temperature control section 19 consists of a fuse 14 and a control element, such as a thermostat 12, which are wired in series, and an electric circuit as shown in FIG. The heating wires 17b and 17c wired to the power source selector switch 21 and the lead wire 18 connecting these
It is composed of. Further, the power supply changeover switch 21 has a COM. terminal, a NO terminal, and an NC terminal, and the COM. terminal and NO terminal are normally connected. Also, the COM of the thermostat 12.
The terminal is connected to the power source 20, the NC terminal is connected to the heating wire 17c, and is normally connected to the COM. terminal.
It is connected to the NC terminal.

Therefore, according to the present invention, when the COM. terminal and the NC terminal of the power source selector switch 21 are connected and the electric circuit is closed, the electricity from the commercial power source 20 passes through the fuse 14 and is energized to the heating wire 17b. In addition, the COM. terminal of the thermostat 12 and the N.
C. The heating wire 17c is energized through the terminal.
Therefore, the heating wires 17b and 17c are heated.

FIG. 3 shows the temperature change on the hot plate 3 when the heating wires 17b and 17c are heated, with temperature on the vertical axis and time on the horizontal axis, where A shows the temperature at the heating wire 17b. Diagram B is a temperature diagram at the heating wire 17c. The temperature diagram A shows a constant temperature as the heating wire 17b is continuously energized and heat is radiated to the outside, and the temperature diagram B shows the temperature of the thermostat 12.
As a result, the current supply to the heating wire 17c becomes discontinuous at a predetermined temperature, so that the temperature fluctuates up and down within a certain temperature range.

(Effects of the invention) As explained above, according to the invention, in a show case that is equipped with a heater that generates heat by electric resistance and is provided with a hot plate on which products are placed at the lower part of the greenhouse, the periphery of the hot plate A first heater is disposed near the center, and a second heater is disposed near the center, and the second heater has a control element that opens the electric circuit of the second heater at a predetermined temperature, so that the heat dissipation effect is large. Continuous heating is performed by the first heater disposed at the peripheral edge of the hot plate, and temperature control is performed by energizing the second heater intermittently by the control element. Therefore, the surface temperature of the hot plate can be made uniform, and the temperature of the product placed on the hot plate can be maintained at a desired temperature. Therefore, the quality of the product can be maintained and its sales can be promoted.

[Brief explanation of the drawing]

1 to 3 show an embodiment of the show case according to the present invention, in which FIG. 1 is a plan view of a plate heater, FIG. 2 is an electric circuit diagram of a heating wire, and FIG.
The figures are temperature diagrams of the hot plate, Figures 4 to 8.
The figures show a conventional show case; Fig. 4 is a front view of the show case, Fig. 5 is a perspective view of the hot plate, Fig. 6 is an assembled view of the hot plate, and Fig. 7 is an assembled view of the hot plate.
The figure is a plan view of the plate heater, and FIG. 8 is an electric circuit diagram of the heating wire. In the figure, 3... hot plate, 12... control element (thermostat), 17b... first heater (heating wire), 17c... second heater (heating wire),
B...Green room.

Claims (1)

[Claims for Utility Model Registration] (1) In a show case that is equipped with a heater that generates heat due to electrical resistance and is provided with a hot plate on which products are placed at the bottom of a greenhouse, the periphery of the hot plate is continuously energized. a first heater that is energized intermittently and a second heater that is energized intermittently near the center, and a control element that opens the electrical circuit of the second heater and energizes the heater intermittently when the temperature is higher than a predetermined temperature. This case is characterized by: (2) The show case according to claim 1, wherein the control element is a thermostat.