JPS6347969Y2 - - Google Patents

Description

[Detailed explanation of the idea] (b) Industrial application fields The present invention relates to a defrost control device for a vending machine.

(b) Conventional technology Vending machines that cool and sell products are known to have a defrost heater that is activated by a timer so that the cooler can be defrosted periodically. It is shown in Utility Model Publication No. 47-21482.

(c) Problems that the invention aims to solve However, especially in vending machines that store frozen products such as ice cream, when the defrosting operation and product loading work overlap, the heat of the defrost heater due to the defrosting operation and the product loading work overlap. When the front door is opened during loading operations, the temperature inside the refrigerator may rise rapidly due to the outside air temperature, which may cause the product to melt and become deformed. Further, a similar problem occurs when the defrosting operation is started immediately after the product loading operation is completed.

For this reason, the present invention is designed to stop defrosting immediately when loading a product during defrosting operation, and to not perform the defrosting operation for that time if the defrosting time comes during or immediately after loading. The present invention provides a defrost control device for a vending machine that does the following.

(d) Means for solving the problem The present invention provides a vending machine equipped with a cooler with a defrost timer that switches the contacts of its own switch for a predetermined time at predetermined intervals, and a defrost timer that switches the contacts of its own switch for a predetermined time at predetermined intervals, and a defrost timer that switches the contacts of its own switch for a predetermined time at predetermined intervals. Then, the first defrost relay is enabled to be energized via the timer switch, and the demagnetization is delayed by the delay means even if the timer performs a predetermined integration and the contact of the switch is switched, and the first defrost relay is delayed by the delay means. a second defrost relay that is energized through the switch of the first defrost relay and self-maintained through its own switch;
a defrost heater that is energized while the defrost relay is energized; a first operating switch that operates based on an operation related to product loading to demagnetize the second defrost relay; a second operating switch that operates in conjunction with the second operating switch; and when the timer reaches a predetermined time while the second operating switch is operating, it is energized via the timer switch and is self-maintained; It consists of a defrost release relay that prohibits the excitation operation of the defrost relay.

(E) Operation When loading a product while the defrost heater is operating, the first operating switch is activated to cut off the energizing circuit of the defrost heater and stop the operation of the defrost heater. In addition, when the timer reaches a predetermined time, if the second operating switch is operated during the loading operation, the defrost release relay is energized via the timer switch and self-holds, and the first defrost Prohibits the excitation operation of the release relay. Even if the first operating switch is reset due to the end of the loading operation while the timer switch is operating, the first defrost relay is not energized, so the second defrost relay is not energized and the defrost heater is activated. is prohibited.

(f) Examples An embodiment of the present invention will be described below in detail based on the drawings.

First, 1 and 2 are AC power lines, and 3 is a defrost timer that is constantly energized, and the switch 3A is turned on every predetermined time, for example, every 8 hours, for a predetermined time, for example, 10
The C contact is kept closed from the B contact for a minute. The b contact of the switch 3A is connected to the coil 4A of the defrost relays A and 4 through a diode D and resistors R1 and R2, and is also connected to the coil 7A of the defrost release relay 7. Defrost release relay 7
has a coil 7A and switches 7B and 7C, the coil 7A is connected to the line 2 via the operating switch 6A, and the a contact of the switch 7B is connected to the line 2.
The b contacts are respectively connected to the actuating switch 6A, and the switch 7C has one end connected to the coil 4A and the other end connected to the line 2. The defrost relay A, 4 has a coil 4A and a switch 4B.
The contact is connected to the c contact of the switch 3A, and the b contact is connected to the coil 5A of the defrost relay B, 5 and the a contact of the switch 5B. Also, capacitor C is resistor R
2 and coil 4A in parallel. The defrost relays B and 5 have a coil 5A and switches 5B and 5C, and the coil 5A is connected to line 2 via an operating switch 6B and a return thermoswitch 8, and the b contact of switch 5B is connected to line 1 and switch 5C. The a contact of the switch 5C is connected to the line 1, and the b contact of the switch 5C is connected to the line 2 via the defrost heater 9. The actuation switches A, 6A and the actuation switches B, 6B are
The interlocking switch may be, for example, a door switch that is activated when a front door forming the front face of the ice cream vending machine is opened, or a loading switch that is manually operated when loading the machine. The return thermoswitch 8 opens when the surface temperature of the cooler exceeds 8°C, and closes when it falls below -2°C, and the defrost heater 9 removes frost attached to the cooler. 10 is a fixed point thermoswitch that opens when the surface temperature of the cooler is 0℃ or higher and closes when the surface temperature of the cooler is below -13℃.One end is connected to the c contact of the switch 5C, and the other end is connected to the cold air inside the storage. It is connected to the line 2 via a circulation electric fan motor 11. A temperature control thermoswitch 12 and a compressor 1 are connected to the series circuit of the fixed point thermoswitch 10 and the fan motor 11.
3 series circuits are connected in parallel. This temperature control thermoswitch 12 is installed inside the storage for storing ice cream, and closes when the internal temperature is -17°C or higher, and opens when the internal temperature is -21°C or higher, maintaining the internal temperature at approximately -19°C. Compressor 1
It controls 3.

The operation of the above configuration will be explained below.

First, when voltage is applied to power lines 1 and 2,
Since the temperature of the cooler is 0°C or higher, the fixed point thermoswitch 10 is open, and the temperature control thermoswitch 12 is -17°C or higher, so the line 1 - the c contact of switch 5C - the temperature control thermoswitch 12 - the compressor 13 - With the closing of line 2, the compressor 13 is energized and started. Then, the temperature of the cooler eventually becomes -13° C. or less and the fixed point thermoswitch 10 is closed, so the electric motor 11 for circulating cool air inside the refrigerator starts operating with a delay, and the inside of the storage is cooled. And temperature control thermo switch 1
2 opens at -17°C or higher, opens at -21°C or lower, and the compressor 13 operates.
The inside of the storage room is kept at approximately -19°C even when the equipment is stopped.

When the defrost timer 3 has passed a predetermined period of time, for example 8 hours, the switch 3A changes to the b contact, so the defrost relays A and 4 are energized and the switch 4B changes to the b contact, and the capacitor C is charged. be done. and a predetermined defrost preparation time, e.g. 10
After 3 minutes, the defrost timer 3 returns the switch 3A to the C contact, but the capacitor C
Since defrost relays A and 4 continue to be energized for the discharge time of
A's c contact - switch 4B's b contact - coil 5A
- Operating switch B, 6B - Return thermo switch 8
- Energize in the closed circuit of line 2. Even when the capacitor C has finished discharging, the defrost relays B and 5 are self-maintained via the b contact of their own switch 5B. By energizing the defrost relays B and 5, the switch 5C is changed to a B contact, so the compressor 1
3 and the cold air circulation electric fan motor 11 are stopped, and the defrost heater 9 is energized and begins to remove the frost that has adhered to the cooler. Eventually, the frost is removed from the cooler and the surface temperature of the cooler increases.
When the temperature exceeds .degree. C., the return thermoswitch 8 is opened. Then, the self-holding circuit of the defrost relays B and 5 is released, and the switch 5C returns to the c contact, and at this time the temperature inside the storage compartment also rises to -17
Since the temperature is above .degree. C., the temperature control thermoswitch 12 is closed, and the compressor 13 is energized and activated. However, the cold air circulation electric fan motor 11 does not start at the same time because the fixed point thermo switch 10 is open because the surface temperature of the cooler is 0° C. or higher. Of course, the surface temperature of the cooler eventually dropped to -13℃.
When the temperature reaches , the fixed point thermo switch 10 closes, and the fan motor 11 starts operating.

Therefore, since the electric fan motor 11 is started after the temperature of the cooler has sufficiently decreased, warm air is not sent into the storage, so the ice cream in the storage does not melt and maintains its quality. It is something.

Next, a case will be described in which the manager attempts to load the contents while the cooler is being defrosted.

When I open the front door to load it,
Actuation switches A and 6A are closed, and actuation switches B and 6B interlocked therewith are opened. At this time, switch 5
The defrost relays B and 5, which were self-held via the B contact of B, are demagnetized, the defrost heater 9 is de-energized, and the compressor 13 is energized, and when the surface temperature of the cooler falls below -13°C, it becomes electrically powered. fan motor 1
1 also drives. In other words, if an attempt is made to load the contents during defrosting, defrosting is immediately stopped so that the temperature increase due to defrosting will not be added to the internal temperature increase due to loading.
Ice cream does not melt.

Next, we will describe the operation when loading a product during the operation period of the defrost timer 3 immediately before starting defrosting, in other words, during the defrost preparation time when the switch 3A is at contact b. At this time, defrost relays A and 4 are energized, but when the front door is opened for loading, operating switches A and 6A are closed, so defrost release relay 7 is energized and switch 7B is activated. In order to self-hold via the switch 7C, the defrost relays A and 4 are demagnetized. In this state, even if the switch 3A of the defrost timer 3 returns to the c contact after the predetermined defrost preparation time has elapsed, the defrost relays A and 4 are demagnetized, so it is likely that the loading of the product has finished. In other words, whether the front door is closed or open, the defrost relays B and 5 are not energized and the defrost heater 9 is not energized. Of course, when the switch 3A returns to the c contact, the defrost release relay 7 is demagnetized. Thereafter, when the front door is closed upon completion of loading, the operating switches 6A and 6B return to their initial states. Therefore, if the product is loaded during the defrost preparation time of the defrost timer 3, even if the switch 3A of the defrost timer 3 returns to the c contact, the defrost heater 9 will not be energized, so the product will not be energized during the loading or its end. Since defrosting is not started immediately, the temperature increase due to defrosting is not added to the increase in temperature inside the storage due to loading of products.

(g) Effects of the invention Since the present invention is configured as described above, the defrosting operation and the loading operation do not overlap, and the defrosting operation immediately after the loading operation is also prohibited. Therefore, the internal temperature of the refrigerator does not rise too rapidly, and deformation of frozen products such as ice cream due to melting can be prevented.

[Brief explanation of the drawing]

The figure is a control circuit diagram showing an embodiment of the present invention. 3... Defrost timer, 4... Defrost relay A, 5
... Defrost relay B, 6A, 6B... Operating switch, 7... Defrost release relay, 9... Defrost heater.

Claims (1)

[Scope of utility model registration request] A vending machine with a cooler has a defrost timer that switches the contacts of its own switch for a predetermined time every predetermined time, and when the timer reaches the predetermined time, it can be energized via the timer switch. A first defrost relay whose demagnetization is delayed by a delay means even if the contact of the switch is switched after a predetermined integration, and excitation via the switch of the first defrost relay during the delay by the delay means. At the same time, a second defrost relay is self-held via its own switch, a defrost heater is energized while the second defrost relay is energized, and a defrost heater is activated based on the operation related to loading the product. a first operating switch that demagnetizes the second defrost relay; a second operating switch that operates in conjunction with the first operating switch; A defrost control device for a vending machine comprising a defrost release relay that is energized via a timer switch and self-holds when a timer reaches the time, and prohibits the excitation operation of the first defrost relay.