JPS6339809Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Object of the Invention] (Field of Industrial Application) The present invention relates to a hot water supply control device for, for example, a hot coffee vending machine.

(Prior Art) A vending machine that sells hot coffee in cups houses a hot water tank, and the water in the hot water tank is heated by a heating element to supply a fixed amount at the time of sale. The capacity of hot water tanks used in such vending machines is determined to cover a certain amount of sales, and for this reason, one heating element is insufficient, so two heating elements are arranged to heat the tank. There is something that makes hot water. An example of a vending machine using this technology is Japanese Utility Model Application Publication No. 150400/1983.
This technology consists of a hot water storage tank divided into a first tank equipped with a hot water outlet and a second tank connected to this via a communication path and equipped with a water inlet, and these two tanks are separated separately. is equipped with an electric heater, and only the electric heater of one of the tanks and the first
The system is designed to give priority to the electric heater in the tank.

However, such a vending machine cannot reliably supply hot water at a predetermined temperature when vending operations are performed continuously and intensively. In other words, when the hot water in the first tank is used, the hot water in the second tank is supplied to the first tank, but in this case, if the hot water in the first tank is used continuously and intensively, the hot water in the second tank is supplied to the first tank. , water that is not heated in the second tank may be supplied to the first tank. Here, the first tank equipped with an electric heater that is preferentially energized is capable of supplying hot water at a temperature suitable for vending machines. However, since the first tank is the one that divides the hot water into the first and second tanks and supplies hot water at a temperature suitable for sales, if the sales operation is continuous and concentrated, the water will quickly become suitable for sales. Hot water cannot be supplied.

(Problem to be solved by the invention) When sales operations are performed continuously and intensively as described above, it becomes impossible to supply hot water at a temperature suitable for sales.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a hot water supply control device for a vending machine that is most suitable for continuous and intensive vending, and can reliably supply hot water suitable for vending even when the vending machine operates continuously and intensively.

[Structure of the device] (Means for solving the problem) The present device includes a first heating element at the bottom and a second heating element at the top.
A hot water tank is provided with a heating element and has a water inlet at the bottom and a water outlet at the upper part, a solenoid valve provided at the outlet, and a water temperature near the first heating element that is set in advance by detecting the water temperature. A first heating element control thermostat that turns off above this temperature and turns on below this temperature, and a second heating element that detects the water temperature near the heating element and turns off when it reaches the boiling point and turns off at a temperature considerably lower than this boiling point. A second heating element control thermometer that is turned on; an appropriate temperature thermometer that is installed near the hot water outlet and determines whether the temperature of the hot water discharged from the hot water outlet is suitable for sale; a first relay with a normally open contact connected to the solenoid valve; a second relay controlled via a second heating element control thermostat and a normally closed contact of the first relay and with a normally closed contact connected to the solenoid valve; a second relay having a holding function; a fourth relay having a self-holding function controlled via the first heating element control thermostat and the other normally closed contact of the first relay; The normally closed contact is connected to the first heating element and the normally open contact is connected to the second heating element.
This is a hot water supply control device for a vending machine which attempts to achieve the above object by including a third relay having a switching contact connected to a heating element.

(Function) By providing such a means, the first heat generation at the bottom of the hot water tank is controlled via the first heating element control thermostat and the normally closed contact of the third relay until the water temperature at the bottom of the hot water tank reaches the set temperature. Electricity is applied to the body to heat it, and then when the water temperature reaches a predetermined temperature, the third relay is activated by the action of the first heating element thermo, and electricity is passed from the first heating element to the second heating element. is switched. Then, when the temperature of the hot water drops to a value that is not suitable for sale and this is determined by the appropriate temperature thermometer, the first and third relays respond to turn on electricity from the second heating element to the first heating element. Switch.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic diagram showing a hot water supply control device for a vending machine.

In the figure, reference numeral 1 denotes a closed type hot water tank, and the hot water tank 1 has a water supply port 2 provided at the lower part thereof, and water discharge ports 3 and 4 provided at two locations at the upper part thereof. Furthermore, the inside of the hot water tank 1 is partitioned into two layers, upper and lower, by providing a partition plate 5 with a plurality of small holes above both the drain ports 3 and 4. Said hot water tank 1
A first heating element 6 is provided to protrude from the inside of the bottom part, and a second heating element 7 is provided to protrude from the inside of the top part. A cistern 8 for adjusting the amount of water in the hot water tank 1 is provided at the upper side of the hot water tank 1, and a pipe 9 communicates the bottom of the cistern 8 with the water supply port 2 of the hot water tank 1. A water supply port 10 is provided on the upper side of the cistern 8, and this water supply port 10 communicates with a water supply 12 via a solenoid valve 11. A float 13 is floated in the cistern 8, and when the water level inside reaches a predetermined water level, a float switch 14 is activated to close the electromagnetic valve 11. A first heating element control thermostat (TH3) is installed on the side of the first heating element 6.
15 are provided. A pipe 16 for releasing steam is provided at the top of the hot water tank 1, and this pipe 16 communicates with the outside air via a heat exchanger 17. A second heating element control thermostat (TH2) 18 is provided near the pipe 16 in the heat exchanger 17. One of the drain ports 3 is connected to a solenoid valve 1.
9 to an auxiliary tank 20, and the other outlet 4 communicates via a solenoid valve 21 to an instant coffee vending mechanism (not shown). The bottom of the auxiliary tank 20 is connected to a pump 23 driven by a motor 22, and the pump 23 is connected to the pipe 2.
4. A booster coil 25 and a pipe 2 that are wrapped around the first heating element 7 and constitute a heat exchanger.
It communicates with a fresh coffee extraction section 27 via 6. A resale prevention thermometer (TH
4) An appropriate temperature thermometer (TH1) 2 is provided on the outside of the side surface located below the drain port 4 in the lower layer.
9 is provided. A float switch 30 is provided in the auxiliary tank 20 to determine the water level so that the tank 20 always contains a certain amount of water.

FIG. 2 is a circuit diagram showing the main parts of the control device of this embodiment. Appropriate temperature thermometer 2 shown in Figure 1 is connected to AC power supply E.
9 (TH1), and the second heating element control thermostat 18 is connected to the normally closed contact X1 of the first relay RY1 and the second relay.
Connected via RY2. In addition, normally closed contact
1 is the self-holding contact Y2 of the second relay RY2.
are connected in parallel. In addition, the first heating element control thermostat 15 is connected to the AC power source E, and the first relay RY1 is connected to the first heating element control thermostat 15.
Another normally closed contact X11 and a fourth relay RY4
are connected via. Note that the self-holding contact Y4 of the fourth relay RY4 is connected in parallel to the normally closed contact X11. Furthermore, a second
heating element control thermo 18 and fourth relay RY
4 normally closed contacts X4 to the third relay RY3,
A fifth relay RY5 having a self-holding contact Y5 via a first heating element control thermostat 15 and a push-button start switch SW, and a resale prevention thermostat 28
and a sixth relay RY6 via a normally closed contact X5 of the fifth relay RY5.

In addition, the first heating element 6 (H1) is connected in series with the first heating element control thermostat 15, the first heating element temperature overrise prevention control thermostat L1, and the normally closed contact X3 of the switching contact of the third relay RY3. At the same time, the second heating element 7 (H2) is connected to the power supply E through the switching contacts of the second heating element control thermostat 18, the second heating element temperature overrise prevention control thermostat L2, and the third relay RY3. It is connected to the power source E via the normally closed contact Y3 in series. A sixth relay is connected between the common terminal of the switching contacts of the third relay RY3 and the AC power supply E.
A series circuit is inserted between normally closed contact X6 of RY6 and dry heating prevention thermostat TH5.

Further, a normally closed contact Y1 of the first relay RY1 and a normally closed contact X2 of the second relay RY2 are inserted in series in a control circuit that controls the energization of the solenoid valve 19 (VL).

The first heating element control thermostat 15 has a temperature of 90°C, for example.
It turns on when below, turns off when it exceeds 90℃, and the second
The heating element control thermo 18 turns on at temperatures below 60°C and turns off when the temperature exceeds 100°C (boiling point), and the resale prevention thermo 28 turns on at temperatures below 63°C, for example, and turns off when the temperature exceeds 100°C (boiling point).
The appropriate temperature thermostat 29 is set to turn off when the temperature exceeds 85°C, and turn on when the temperature exceeds 85°C, for example.

In the control device configured in this manner, when a predetermined amount of coins and a selection switch are inserted while power is being supplied, the instant coffee vending mechanism opens the solenoid valve 21 for a predetermined period of time to dispense a predetermined amount of coffee. In addition to discharging the hot water, instant coffee powder, other sugar, and cream are released to sell instant coffee by the cup. In addition, when a predetermined amount of coins and a selection switch are inserted while power is being supplied, the fresh coffee vending mechanism opens the solenoid valve 19 for a certain period of time, operates the motor 22 for a certain period of time, and operates the fresh coffee vending mechanism for a certain period of time. Coffee powder is supplied to a fresh coffee extracting part 27 to obtain a coffee extract, and sugar and cream are released into the coffee extract to sell fresh coffee in a cup.

Next, the operation of the control device of this embodiment when heating the water supplied from the cistern 8 into the hot water tank 1 will be explained using the timing diagram of FIG. 3.

Assuming that the water temperature in the hot water tank 1 is now 30°C, when a power switch (not shown) is turned on at time t ₀ and power is supplied to this control device from the AC power supply E, the water temperature will be 30°C. So each thermometer 15,
18 and 28 are turned on. As a result, the second relay RY2 connected to the second heating element control thermostat 18
Then, the fourth relay RY4 connected to the first heating element control thermostat 15 and the sixth relay RY6 connected to the resale prevention thermostat 28 are turned on. Note that the second and fourth relays RY2 and RY4 are self-held by self-holding contacts Y2 and Y4, respectively, and therefore remain on unless the thermostats 15 and 18 are turned off again. Therefore, simply by turning on the power, the normally closed contact X6 of the sixth relay RY6 is opened, and no current flows through the first and second heating elements 6 and 7.

Next, when the push-button start switch SW is turned on at time t1, the fifth relay RY5 is turned on since the thermostat 15 is in the on state. This fifth
Relay RY5 is self-held at self-holding contact Y5 until thermostat 15 is turned off. the result,
The normally closed contact X5 of this fifth relay RY5 opens, the sixth relay RY6 turns off, and the normally closed contact X6
is closed. Therefore, a current flows through the first heating element 6 provided at the lower part of the hot water tank 1 to a temperature of 30°C.
water is heated.

Next, when the water temperature reaches 63° C. at time t2, the resale prevention thermometer 28 is turned off. When the water temperature further rises and reaches 85°C at time t3, the appropriate temperature thermostat 29 installed near the solenoid valve 21 is turned on, and the first
relay RY1 turns on. As a result, the normally closed contacts X1 and X11 open, but the second and fourth relays RY2 and RY4 maintain their self-holding state. When the appropriate temperature thermometer 29 is turned on, power supply to an instant coffee selling mechanism (not shown) is started, and instant coffee can be sold.

Furthermore, when the water temperature reaches 90°C at time t4,
The first heating element control thermostat 15 is turned off. When this first heating element control thermometer 15 is turned off, the fourth and fifth relays RY4 and RY, which were self-holding,
5 turns off and the normally closed contact X4 of the fourth relay RY4
is closed. Therefore, the third relay RY3
turns on, and the switching contact of this relay RY3 switches from the normally closed contact X3 side to the normally open contact Y3 side. As a result, energization to the first heating element 6 is stopped, and on the contrary, energization to the second heating element 7 is started. Note that when the fifth relay RY5 is turned off, the normally closed contact X5 is closed, but since the resale prevention thermometer 28 has already been turned off at t2, the sixth relay RY6 maintains the off state.

When the second heating element 7 is energized, the hot water tank 1
The water temperature in the upper layer of the water rises rapidly at time t5.
Reaches boiling point of 100℃. Thus, the steam in the hot water tank 1 escapes to the outside via the pipe 16 and is cooled by the heat exchanger 17 on the way. As a result, the detected temperature of the second heating element control thermostat 18 exceeds 100° C. and is turned off. In this way, the power supply to the second heating element 7 is stopped. When the second heating element control thermometer 18 turns off, the second relay RY, which had been self-holding until now,
2 is turned off, and the normally closed contact X2 of the second relay RY2 inserted in the control circuit of the solenoid valve 19 is closed. The normally closed contact Y1 of the first relay RY1 is t3
Since it is closed when the water temperature reaches 85℃, the entire control circuit is closed. Therefore, the electromagnetic valve 19 can be opened and closed by a control signal from the vending mechanism, so that the fresh coffee vending mechanism can operate.

After that, the water temperature in the upper layer of hot water tank 1 decreases,
When the steam is no longer released, the second heating element control thermostat 18 is turned on again, and the second heating element 7 is operated again. By repeating the operation of the second heating element 7 intermittently in this way, the water temperature in the upper layer of the hot water tank 1 is maintained at approximately 98°C to 100°C. On the other hand, the water temperature in the lower part of the hot water tank 1 is maintained at a little less than 90° C. with only a few shots of the second heating element 7. After that, from time t5, when coffee sales are carried out continuously and the hot water in the hot water tank 1 is released, water is supplied from the cistern 8 to the water inlet 2 of the hot water tank 1 via the pipe 9, and as a result, the hot water tank 1 The temperature in the lower layer of the room decreases. Then, when the temperature reaches 90°C, the first heating element control thermostat 15 is turned on, and when the temperature falls below 85°C at time t6, the appropriate temperature thermostat 15 is turned off and the sale of instant coffee is stopped.
When the appropriate temperature thermometer 15 turns off, the first relay RY
1 is turned off, normally closed contacts X1 and X11 are closed,
The second relay RY2 and the fourth relay RY4 are turned on. Therefore, the normally open contact Y1 and the normally closed contact X2 inserted in the control circuit of the solenoid valve 19 (VL) are opened, and the operation of the fresh coffee vending mechanism is also stopped.

On the other hand, when the fourth relay RY4 is turned on, the normally closed contact X4 is opened, the third relay RY3 is turned off, and the switching contact of this relay RY3 is changed to the normally open contact Y3.
Switch from the side to the normally closed contact X3 side. As a result, the second
energization to the first heating element 7 is stopped, and energization to the first heating element 6 is started.

However, when the water temperature in the hot water tank 1 drops to 85°C at time t6, the sale of instant coffee and fresh coffee is stopped, and new cold water is not supplied from the water supply port 2. Temperature drop is suppressed. Then, from time t6, the first heating element 6 heats the water in the hot water tank. This condition is 30 minutes after first turning on the power.
The heating conditions are the same as those from time t3 when heating water at .degree. Therefore, it is heated to the boiling point (100° C.) in the same process as t3 to t5. Note that the appropriate temperature thermostat TH1 is turned on immediately when the water temperature returns to 85°C or higher, and the first relay RY1 is also turned on accordingly.

Next, when you open the power switch (not shown),
Since the power supply to the first and second heating elements 6 and 7 is stopped, the water temperature in the hot water tank 1 gradually decreases. The prevention thermostat 28 is turned on. However, from now on, when the power is turned on again, the sixth relay RY6 is turned on and the normally closed contact X6 is opened, so that the first and second heating elements 6 and 7 are no longer energized. . To turn on the power again, you must operate the start switch SW.

Incidentally, for instant coffee, it is sufficient to supply hot water at about 85°C, but for fresh coffee, since the coffee is obtained by extraction, water at a temperature close to the boiling point is desirable. For this boiling point, pump 2
The hot water discharged in step 3 is heated via the booster coil 25 by the second heating element 7 and the high temperature hot water in the upper layer to obtain hot water at a temperature close to the boiling point.

In this embodiment, the first heating element 6 is used to heat the lower part of the hot water tank until it reaches 90°C, and when the temperature reaches 90°C or higher, the second heating element 6 is used.
and the temperature detected by the appropriate temperature thermometer 29 is 85℃.
When the temperature is below, the first heating element is heated again, so a large amount of hot water is used in a short period of time, and as a result of introducing a large amount of water from the water supply port 2, the hot water tank 1
Even if the water temperature inside the container drops below a temperature suitable for sale, the reheating conditions can be set to the same conditions as the initial heating conditions when heating from cold water, making it possible to keep the time required for heating and temperature rise characteristics almost constant. It is. Therefore, uniform and stable sales operations can be performed. Especially when selling in a concentrated manner, the first heating element at the bottom heats the hot water and sends it to the upper layer, so even if a large amount of hot water is used, the supply of hot water is reliable, and the number of sales can be increased. Good response to fluctuations.

Furthermore, the above embodiment can also provide the following effects. In other words, since the heat generating operation is not performed on two elements at the same time, and only one of them is always active, the amount of power supplied is sufficient as long as it corresponds to one heating element, and a power supply with a small amount of power can be used. . Further, the temperature of the hot water used for instant coffee and fresh coffee can be changed, and in particular, the hot water for fresh coffee can be brought to a temperature close to the boiling point by the booster coil 25. That is, sufficiently heated hot water can be supplied to the fresh coffee extraction section 27.

In addition, in the above embodiment, a device capable of emitting both hot water for instant coffee and hot water for fresh coffee was described, but the invention is not necessarily limited to this, and a device capable of emitting only hot water for fresh coffee. It may be. Further, each set temperature may be freely changed without changing the gist of the invention.

[Effects of the invention] As described in detail above, according to the invention, hot water supply control for a vending machine that is optimal for continuous and intensive vending can reliably supply hot water suitable for vending even during continuous and intensive vending operations. equipment can be provided.

[Brief explanation of drawings]

Fig. 1 is a schematic configuration diagram showing a hot water supply control device for a vending machine according to an embodiment of the present invention, Fig. 2 is a circuit diagram showing main parts of the control device, and Fig. 3 is an operation of the control device. FIG. 1... Hot water tank, 2... Water supply port, 3, 4...
Water outlet, 6...first heating element, 7...second heating element, 15...first heating element control thermostat, 18...
Second heating element control thermo, 19...Solenoid valve, 29
...Appropriate temperature thermometer, RY1 to RY6...1st to 6th
relay.

Claims (1)

[Scope of utility model registration request] a hot water tank having a first heating element at the bottom and a second heating element at the top, a water supply port at the bottom and a hot water outlet at the top; a solenoid valve provided at the water drain port; A first heating element control thermostat that detects the water temperature near the heating element and turns off when the temperature exceeds a preset temperature and turns on when the temperature falls below the preset temperature; a second heating element control thermo that turns off when the boiling point is reached and turns on at a temperature well below the boiling point;
an appropriate temperature thermometer provided near the outlet for determining whether the temperature of the hot water discharged from the outlet is suitable for sale; and a normally open contact responsive to the appropriate temperature thermostat connected to the solenoid valve. a second relay having a self-holding function controlled via the second heating element control thermostat and a normally closed contact of the first relay, the normally closed contact being connected to the solenoid valve; a fourth relay having a self-holding function controlled via the first heating element control thermostat and another normally closed contact of the first relay; and the second heating element control thermostat; a fourth relay having a switching contact controlled via a normally closed contact of the fourth relay and having a normally closed contact connected to the first heating element and a normally open contact connected to the second heating element; 3. A hot water supply control device for a vending machine, characterized in that it is equipped with the following relays.