JP3263909B2 - Induction heating device for canned vending machines - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an induction heating apparatus used for a vending machine for cans, particularly beverage cans, and more particularly to an improvement in a can type discriminating mechanism and a heating control mechanism.

[0002]

2. Description of the Related Art Recently, an automatic vending machine for hot beverage cans has been provided with an induction heating device for instantly heating only a desired beverage can at the time of sale.

[0003] FIG. 2 shows a main configuration of such an induction heating device. The induction heating device includes a rectifier circuit 12 connected to a commercial AC power supply 10, an inverter circuit 14 connected to the rectifier circuit 12, and a CL oscillation circuit 16 connected to the inverter circuit 14. Reference numeral 16 denotes a series circuit of a condenser 18 and a heating coil 20. Incidentally, reference numeral 24 denotes a phase control circuit.

When the purchaser of the can presses the button of the vending machine provided with the induction heating device, the can 22 is introduced into the heating coil 20 and the switch is turned on, so that the high-frequency AC power is supplied from the AC power supply 10. Electric current flows.

The AC current is rectified by the rectifier circuit 12 into a DC current, and further converted by the inverter circuit 14 into a high-frequency AC current.

The high frequency current from the inverter circuit 14 is applied to the CL oscillation circuit 16 to
6 starts to oscillate, the high-frequency current output from the circuit 16 is conducted to the heating coil 20, an induction current is generated in the metal can of the can 22, and the can itself generates heat. The entire 22 is heated.

A heating time is set so that the can 22 is heated to an appropriate temperature, and a high-frequency current is supplied from the inverter circuit 14 to the heating coil 20 based on the heating time, so that the can 2 is heated.
2 will be heated to an appropriate temperature.

[0008]

By the way, as for the heating time of the can, if there is only one kind of cans sold by one vending machine, a fixed heating time suitable for the can type is set. You should keep it.

However, there are many types of cans sold in vending machines in recent years, and there are various types of cans such as structures, capacities and materials. That is, in a can structure, a two-piece can formed by drawing and ironing or deep drawing (or stretching), a three-piece can in which a can body side seam is joined by welding or an adhesive, and a can capacity of 190 g can (Approximately 53
mm, height about 103mm), 250g can (about 53m in diameter)
m, height about 130mm) and 340g can (about 66m in diameter)
m, height of about 120 mm), and can materials (can body materials) such as aluminum cans and steel cans.

The main types of cans are aluminum 2-piece 190g cans formed by drawing and ironing, and 250g aluminum cans.
Can, 340g can, 3-piece 190g steel canned with seam side joint by resistance seam welding, 250g
There are eight types: cans, 340 g cans, 2-piece 250 g cans formed by drawing and ironing, and 340 g cans.
From the can diameter, about 53mm (202 diameter), about 66m
m (211 diameter).

In the induction heating apparatus, if cans of different types are uniformly heated by a single heating coil for a certain period of time, there is a problem that depending on the type of can, the can temperature is not heated to an appropriate temperature. For example, at the same capacity, a three-piece can is hotter than a two-piece can, and an aluminum can is less likely to be heated than a steel can.

For this reason, the heating time must be controlled according to the type of the can introduced into the heating coil. However, it is very difficult to automatically and accurately determine the structure, capacity, material, etc. of the type of the can accurately. is there.

The present invention has been made in view of such problems of the prior art, and an object of the present invention is to automatically discriminate various kinds of cans introduced into a heating coil, and to perform appropriate heating for the can types. An object of the present invention is to provide an induction heating device capable of controlling time.

[0014]

In order to achieve the above object, an induction heating apparatus according to the present invention comprises a sensor, a plurality of CL oscillating units, a high-frequency power supply unit, a changeover switch, a switch changeover unit, and a current value detecting unit. , An integrator, a can type determination unit, and a heating time control unit.

[0015] The sensor detects the diameter of the can that is the object to be heated.

The CL oscillating section comprises a plurality of heating coils into which the can is introduced according to the diameter of the can detected by the sensor, and capacitors connected to each of the heating coils.

The high-frequency power supply outputs a high-frequency current corresponding to the impedance of the cans introduced into the heating coil to the CL oscillator.

The changeover switch connects the high frequency power supply unit to one of the plurality of CL oscillation units.

The switch changeover unit switches the changeover switch to the CL oscillating unit side having the heating coil into which the can is introduced, based on the can diameter value detected by the sensor.

The current value detection section detects a high frequency current value output from the high frequency power supply section.

The integrator integrates the output current value detected by the current value detecting section.

The can type discriminating section discriminates the can type of the can introduced into the heating coil based on the current integrated value integrated by the integrator and the can diameter value detected by the sensor.

The heating time control section controls the ON time of the high frequency power supply section based on the can type determined by the can type determination section.

The output current value detected by the current value detection unit is compared with a predetermined current value set in advance, and the output from the high-frequency power supply unit is controlled so that the output current value does not exceed the predetermined current value. A current control unit for controlling the high-frequency current to be generated.

[0025]

As described above, there are two types of canned beverages currently marketed in Japan: steel cans and aluminum cans, 190 g cans, 250 g cans, and 340 g cans, and 2-piece cans and 3 piece cans. Although there are extremely many types depending on each combination, the main ones are also eight types as described above, and two types of can diameters (202 diameter, 211
Diameter).

When a high-frequency current is output to the coil to heat the can introduced into the heating coil, the effective current value of the high-frequency current (synonymous with the current integral value) is introduced into the coil. The impedance is determined by the impedance of the cans. The impedance of the eight types of cans is shown in FIG. 3 (Since the pure resistance and the impedance are correlated, it is necessary to know the impedance from the value of the pure resistance. Can be).

The above 8 having different impedances
When the seed can was introduced into a single heating coil (here, a 211-diameter coil was used), the value of the high-frequency current flowing through the coil at a predetermined time was measured as shown in FIG. 4 ((A) in the figure). To (H) correspond to cans (A) to (H) in FIG. 3). Telegraph uses 5KVA.

This means that when a single heating coil is used, the current value (current integral value) of the high-frequency current flowing through the coil in a predetermined time is approximated and overlapped in some types of cans. This means that accurate can type determination cannot be performed from the current value.

On the other hand, FIG. 5 uses two heating coils (202 diameter and 211 diameter) corresponding to two kinds of can diameters.
In the case where the eight types of cans are respectively introduced into the heating coils corresponding to the can diameters, the currents flowing in each coil for a predetermined time are shown. The power supply uses 5KVA.

FIG. 5 shows that the current integrals of the five types of cans in the 202-diameter coil are clearly different from each other.
It is known that the current integrals of the three types of cans in the 11-diameter coil are also clearly different from each other.

The present invention has been made based on such new knowledge, and a plurality (at least 20) corresponding to the can diameter has been developed.
Two heating coils for two-diameter cans and 211-diameter cans)
A CL oscillation circuit is configured for each of them, and accurate can type discrimination can be performed based on the integrated current value and the can diameter of the CL oscillation circuit.

The heating time control unit controls the high-frequency power supply unit to be ON for a preset heating time for each can type based on the determination result of the can type. It becomes possible to heat all cans of a large number of cans composed of various combinations of structures, materials and capacities introduced into the coil to an appropriate temperature.

Each can is introduced into an appropriate heating coil according to a detection signal of a sensor for detecting the can diameter of the can. The detection signal is also input to a switch switching section, and the can is introduced. The changeover switch is switched so that the heating coil and the high-frequency power supply unit are connected, and a high-frequency current is output to the heating coil.

Further, the induction heating device controls the high-frequency current output from the high-frequency power supply unit so that the output current value detected by the current value detection device does not exceed a predetermined current value, so that the low impedance However, no excessive current flows through the heating coil.

[0035]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic configuration diagram of an induction heating apparatus according to the present embodiment. The part corresponding to FIG.
Are added, and the description is omitted.

This induction heating device is connected to a commercial AC power supply 110.
A rectifier circuit 112, an inverter circuit 114 serving as a high-frequency power supply unit, and a CL oscillating unit 116 (this includes a first CL oscillating circuit 116a including a series circuit of a first capacitor 118a and a first heating coil 120a, and a second capacitor 118).
b and a second circuit composed of a series circuit of the second heating coil 120b
L oscillation circuit 116b).

Either the first CL oscillation circuit 116a or the second CL oscillation circuit 116b can be connected to the inverter circuit 114 by the changeover switch 126.

The diameter of the can 122, which is the object to be heated, is detected by a sensor 128.
It is introduced into either the heating coil 120a or the second heating coil 120b. Although not shown, these heating coils are covered with an insulating material so as not to be short-circuited even when they come into contact with the can 122 introduced therein.

In this embodiment, two limit switches are used as the sensor 128. That is, the can is allowed to proceed in the direction of the can axis when heading to the heating coil, and two limit switches are passed through the passage, and if a can having a diameter of 211 passes, the contacts of the two limit switches are contacted. Are both in contact with the can body and the switch is turned on.
Even if a can with a diameter of 02 passes, only one contact of the limit switch is placed at a distance that allows contact with the can body.
The contact between the contacts of the limit switches and the can body detects the passage of the can. To detect.

As described above, the diameter of currently marketed cans is about 53 mm (202 diameter) and about 66 mm (21 mm).
1 diameter), the heating coil is also 2 in this example.
Seeds were prepared. That is, the heating coil 120a is
120b is for 211-diameter cans.

On the output side of the detection signal of the sensor 128, a switch switching section 130 and a can type discriminator 132 are provided.
Further, a heating time control unit 140 to which a signal from the can type discriminating unit 132 is input is provided.

The switch switching unit 130 includes a sensor 128
The switching of the changeover switch 126 is performed based on the detection signal.

The heating time control section 140 is a heating ON / OFF for switching the output power of the inverter circuit 114.
First AND gate 14 to which switch 142 is connected
4 is connected.

A current value detector 134 is provided at a connection point of the inverter circuit 114CL oscillating unit 116, and a detection signal of the current value detector 134 is input to the can type discriminating unit 132 via the integrator 136. At the same time, it is also input to the phase control circuit 124 and the current control circuit 138.

The phase control signal from the phase control circuit 124 is passed through a second AND gate 146, and the signal from the current control circuit 138 is passed through a third AND gate 148 and the gate 146.
4 is input.

When the selling button is pressed in the canned vending machine in which the induction heating device constructed as described above is incorporated, the canned item 122 indicated by the button is detected by the sensor 128.
It moves to the vicinity and the diameter of the can 122 is detected by the sensor 128.

On the basis of the detection result of the sensor 128, the can is put into the first heating coil 120a or the second heating coil
0b. More specifically, a can having a diameter of about 53 mm (capacity 190 g, 250 g) is provided to the first heating coil 120a by a diameter of about 63 mm (capacity 340).
g) cans are respectively introduced into the second heating coils 120b.

The detection signal of the sensor 128 is also input to the switch switching section 130 and the switch switching section 13
From 0, a switching instruction is sent to the changeover switch 126. In other words, the can 122
Is introduced into the first heating coil 120a (202-diameter coil), the first CL oscillation circuit 116a becomes a closed circuit, and the can 122 becomes the second heating coil 120b.
(211 diameter coil), the changeover switch 12 is set so that the second CL oscillation circuit 116b becomes a closed circuit.
6 is performed.

Thus, the can 122 is made of the first heating coil 12
0a or the second heating coil 120b is introduced, the heating ON / OFF switch 142 is turned on, and the high frequency current from the inverter circuit 114 is closed.
The can 122 is heated by being added to the oscillation unit 116.

Here, as described above, the can type of the can 122 varies in terms of material, structure, and capacity, and the type of can that has been introduced with the first heating coil 120a or the second heating coil 120b is determined. The heating must be controlled with a heating time corresponding to the type of the can.

Therefore, in the present embodiment, the can type is determined based on the current integrated value of the CL oscillating unit 116 in a closed circuit and the can diameter detected by the sensor 128.

That is, as shown in FIG. 5, when a can having a diameter of 202 is introduced, the first heating coil 120a (20
The current value and the current integral value flowing through the two-diameter coil) obviously differ depending on the type of the can 122 introduced.
When the 11-diameter can is introduced, the second heating coil 120b
The value of the current flowing through the (211 diameter coil) and the current integrated value also obviously differ depending on the type of the can 122 introduced.

For this reason, the current value flowing through the first heating coil 120a or the second heating coil 120b is detected by the current value detector 134, and the detection signal of the can diameter in the sensor 128 is sent together with the current value to the can type discriminating section 132. The can type of the can 122 can be determined from the combination of the can diameter and the current value. Note that the current value detector 13
4 is integrated by an integrator 136 to obtain an integrated value of the current value.
2 is input.

The discrimination signal from the can type discriminating section 132 is input to the heating time control section 140, and the heating signal is inputted to the first AND gate 144 based on an instruction for the heating time preset in the heating time control section 140 according to the can type. A stop signal is output. Therefore, the current from the heating ON / OFF switch 142 is cut off, and the output of the inverter circuit 114 stops.

As described above, according to the diameter of the can 122, the can 1
The first heating coil 120a and the second heating coil
It is possible to determine the can type from the combination of the current value of the high-frequency current flowing through each of the heating coils 120b and the diameter of the can 122, and set and control the heating time according to the can type. It has become possible to heat the can 122 to an appropriate temperature.

Since the can 122 being heated is rotated by a rotating device (not shown), the heat of the can is quickly transmitted to the internal solution.

Further, in this embodiment, the current control circuit 138 controls the high-frequency current flowing through the heating coil 120 so as not to exceed a predetermined power.

The current control circuit 138 includes a current setter 150 in which a predetermined current is set, and a current comparison comparator 1
52, and a holding circuit 154. The current detected by the current value detector 134 and the predetermined current set by the current setting unit 150 are input and compared to the current comparison comparator 152,
When the current value of the current value detector 134 reaches a predetermined current value, a stop (Low) signal is output to the third AND gate 148 via the holding circuit 154. The stop signal cuts off the current supply from the inverter circuit 114 to the CL oscillating unit 116 via the second AND gate 146 to which the signal of the phase control circuit 124 is output.

The stop signal is held by the holding circuit 154, and after a half cycle of the output current frequency of the inverter circuit 114, a signal for releasing the stop signal is output from the phase control circuit 124 to the holding circuit 154. The AND gate 148 is turned ON again, and the current supply to the CL oscillating unit 116 is performed again.

As described above, for example, even when the impedance of the can introduced into the heating coil is low and a very large current tries to flow through the heating coil, the current control circuit 138 cuts off the supply of a predetermined current or more. be able to.

In addition to the method of directly detecting the diameter of the can, the can diameter of the can is detected by utilizing the fact that the can of 211 diameter is different in height and weight from the can of 202 diameter. The diameter of the can may be detected indirectly by detecting the height of the can using a proximity switch or the like, or measuring the can weight by passing the can over a weight sensor such as a load cell.

In order to detect the can height with a photoelectric switch (or proximity switch), the can is made to advance in the axial direction of the can, and a reference photoelectric switch is arranged at a position close to the passage. About 9 each from this photoelectric switch
A photoelectric switch is arranged at a position close to the passage at a distance of 9 mm, about 116 mm, and about 126 mm. When only the reference photoelectric switch and the neighboring photoelectric switch are turned ON for a moment when the can is passed, a 190 g can (202 dia. ), If the reference photoelectric switch and the next photoelectric switch and the next photoelectric switch are in the ON state, it is determined to be 340 g can (211 diameter), and if all the photoelectric switches are in the ON state, it is determined to be 250 g can (202 diameter).

[0064]

According to the induction heating device of the present invention, the type of cans introduced into the heating coil can be accurately discriminated in terms of the structure, material, capacity, etc., and the heating time is adapted to the discriminated can type. Since the heating is controlled, it is possible to accurately heat to an appropriate temperature regardless of the type of the can.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view of an induction heating device according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a main configuration of a conventional induction heating device.

FIG. 3 is a comparative explanatory diagram of pure resistance in different types of cans.

FIG. 4 is an explanatory view showing a can type comparison of an integrated value of a current flowing through a single heating coil.

FIG. 5 is an explanatory diagram of can type comparison of integral values of current flowing through coils when two types of heating coils are used.

[Explanation of symbols]

 114 ... High frequency power supply unit (inverter circuit) 116a, 116b ... CL oscillation circuit 118a, 118b ... Capacitor 120a120b ... Heating coil 122 ... Canned 126 ... Changeover switch 128 ... Sensor 130 ... Switch switching unit 132 ... Detector 136 ... Integrator 140 ... Heating time control unit

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G07F 11/70 H05B 6/06

Claims (3)

(57) [Claims] 1. A sensor for detecting a diameter of a can that is an object to be heated, a plurality of heating coils into which the can is introduced in accordance with the diameter of the can detected by the sensor, and a heating coil connected to each of the heating coils. A plurality of CL oscillating units each including a capacitor; a high-frequency power supply unit that outputs a high-frequency current corresponding to the impedance of the can that has been introduced to the heating coil to the CL oscillating unit; a high-frequency power supply unit and the plurality of CL oscillations A changeover switch for connecting one of the units to a CL oscillation unit having the heating coil into which the can is introduced, based on a can diameter value detected by the sensor; and A current value detection unit that detects a high-frequency current value output from the high-frequency power supply unit; and an integrator that integrates the output current value detected by the current value detection unit. A can type discriminating unit for discriminating a can type of cans introduced into the heating coil based on a current integral value integrated by the integrator and a can diameter value detected by the sensor; An induction heating device for a canned vending machine, comprising: a heating time control unit that performs time control of an ON state of the high-frequency power supply unit based on a can type determined by the determination unit. 2. A plurality of heating coils are provided for a 202-diameter can.
2. The induction heating device for a canned vending machine according to claim 1, which is two for an 11-diameter can. 3. The induction heating apparatus according to claim 1, wherein the output current value detected by the current value detection section is compared with a predetermined current value set in advance, and the output current value is determined by the predetermined current value. An induction heating device for a canned vending machine, comprising a current control section for controlling a high-frequency current output from the high-frequency power supply section so as not to exceed a value.