JPS6319140B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a melting device that continuously melts sucrose by heating it without adding water.

Conventionally, in order to continuously melt sucrose by heating without adding water, a nichrome wire heater 2 was buried in the wall of a rotatable inner heating cylinder 1 with a threaded groove as shown in Fig. An outer heating cylinder 3 is loosely fitted on the outside of the inner heating cylinder 1, a nichrome wire heater 4 is embedded in the wall of the outer heating cylinder 3, and a hopper 5 for charging sucrose is installed in the upper part of the outer heating cylinder 3. Then, sucrose is charged through the hopper 5, and by rotating the inner heating cylinder 1, the sucrose is heated by the nichrome wire heaters 2 and 4 while descending along the threaded groove 6. is melted and discharged from the outlet 7.
Melting devices are known that are designed to allow for greater removal.

In such a conventional melting apparatus, the nichrome wire heater is heated, and then the inner heating cylinder 1 and the outer heating cylinder 3 are heated by heat transfer, so that the entire melting apparatus reaches the desired temperature. It takes a lot of time to raise the temperature, and in order to improve the conduction efficiency compared to a nichrome wire heater, it is necessary to select an expensive material such as copper or aluminum.

In addition, the nichrome wire heaters 2 and 4 are connected to the inner heating tube 1.
Since it is embedded in the outer heating cylinder 3, the inner heating cylinder 1 and the outer heating cylinder 3 naturally have thick walls, and it is possible to raise the outer wall surface of the inner heating cylinder 1 and the inner wall surface of the outer heating cylinder 3 to the desired temperature. It takes longer to transfer heat than a nichrome wire heater. Furthermore, the power supply device becomes complicated in order to supply power to the nichrome wire heater 2 embedded in the rotating inner heating cylinder 1.
The whole thing gets bigger. Moreover, the nichrome wire heater is easily broken, and the nichrome wire heater is
Since it is buried in the outer heating cylinder 3, repair is extremely difficult.

As a result of intensive research to solve the conventional problems as described above, the inventors of the present invention have developed an inner heating tube that has a spiral groove on its outer peripheral surface and is rotatably supported. A sucrose melting device comprising an outer heating cylinder arranged concentrically, a hopper at the upper end between the heating cylinders, and sucrose can be freely inserted between the heating cylinders from the hopper. A heating tube is formed of a magnetic material such as silicon steel or iron, and a coil support tube is provided concentrically on the center side of the inner heating tube, and an inner excitation coil is provided on the outer periphery of the coil support tube, and the outer heating tube is provided with an inner excitation coil on the outer periphery of the coil support tube. A plurality of outer excitation coils are provided at positions shifted in the axial direction on the outer periphery of the cylinder, the outsides of the plurality of outer excitation coils are each covered with a magnetic flux guide made of a magnetic material, and each magnetic flux guide and the coil support cylinder are provided with a magnetic flux guide made of a magnetic material. forms a continuous notch along the axial direction at some location in the circumferential direction,
An AC power source can be freely connected to each of the excitation coils,
It is characterized in that heat is generated by passing an alternating magnetic flux through both heating cylinders by applying the power.

Next, an example of the implementation of the present invention will be described with reference to the drawings from FIG. 2 onwards. In the figure, 10 is an inner heating cylinder, and 11 is an outer heating cylinder. Both heating tubes 1
0 and 11 are provided in a concentric arrangement, and the outer heating cylinder 11
is fixed to the device frame, and the inner heating cylinder 10 is formed so that its outer diameter is in sliding contact with the inner surface of the outer heating cylinder 11, and a thread groove 12 is formed on its outer surface.

The upper end of the inner heating cylinder 10 is longer than the outer heating cylinder 11, and a hopper 13 whose upwardly protruding part is shaped like a truncated cone is disposed on the outside, and the lower end of the hopper 13 is connected to the upper end of the outer heating cylinder 11. inside the lower end of the hopper 13 and both heating cylinders 10,
11 are communicated with each other.

Furthermore, an inner cylinder 14 for shaft support is provided inside the inner heating cylinder 10 in a concentric arrangement, and the two cylinders 10 and 14 are integrated by a connecting portion 14a between their lower ends.
A support shaft 15 is inserted into the inner cylinder 14 and supported by tightening the inward flange portion 14b with a nut 15a. On the other hand, it is rotatably supported by the machine frame of the support shaft 15 via a bearing 16, so that the rotation of the motor can be transmitted although it is not shown. Therefore, the inner cylinder 1 is
The inner heating cylinder 10 is supported through the connecting portions 14a of the four connecting parts 14a, and is rotated by the rotational drive of the support shaft 15.

Both inner and outer heating cylinders 1 arranged as described above
Reference numerals 0 and 11 indicate inner and outer excitation coils 1 which are made of a magnetic material and constitute heating means inside the inner heating cylinder 10 and outside the outer heating cylinder 11, respectively.
7 and 18 are provided.

The magnetic material for both heating cylinders 10 and 11 may be any material that can be used as the core of a coil in a transformer, such as silicon steel or iron, among which carbon steel for machine structures and general structures as defined in the Japanese Industrial Standards. Rolled material etc. are used. Note that stainless steel, which is a semimagnetic material, is not preferable because short circuit current generated by receiving alternating magnetic flux, which will be described later, is weak.

The inner excitation coil 17 is fixed to the machine frame, and the coil support tube 1 is inserted into the inner surface of the inner heating tube 10.
9 , and is wound within a recess formed on the outer surface of this coil support tube 19 .

This coil support tube 19 is made of a magnetic material and is configured to form a closed magnetic circuit as shown by the broken line A in FIG. 2 when an alternating current is passed through the inner excitation coil 17.

On the other hand, a plurality of outer excitation coils 18 are wound around the outer circumference of the outer heating cylinder 11 at intervals in the axial direction, and a magnetic flux guide 20 made of a magnetic material is provided on the outside of each outer excitation coil, that is, on both end surfaces and the circumferential surface. By covering each of the outer excitation coils 18 individually and applying an alternating current to the outer excitation coil 18, a closed magnetic circuit shown by the broken line B in FIG. 2 is constructed.

In addition, 21a and 21b in the figure are the outer excitation coils 18.
This is a positioning ring made of non-magnetic material.
Furthermore, as shown in FIG. 3, each of the plurality of magnetic flux guides 20, the coil support tube 19, and the inner tube 14 has notches 20a, 19a, and 14a continuous along the axial direction at some locations in the circumferential direction. They are formed to prevent a circumferential short circuit current from flowing when each exciting coil 17, 18 is energized.

Next, the operation of the device configured as described above will be explained.

First, an AC power source is connected to both the inner and outer excitation coils 17 and 18, and the spindle 15 is rotated by a motor, and in this state, the sucrose in the hopper 13 is charged.

At this time, an alternating current is applied to the inner excitation coil 17, thereby generating an alternating magnetic flux along the broken line A mentioned above. Due to the generation of this alternating magnetic flux, a circumferential short circuit current flows through the inner heating tube 10 as shown by the broken line C in FIG. 3, thereby generating Joule heat. Heat is also generated due to hysteresis loss of the inner heating tube 10 itself due to the passage of alternating magnetic flux.

Similarly, by applying an alternating current to the outer excitation coil 18, an alternating magnetic flux is generated along the broken line B, resulting in a hysteresis loss of the outer heating cylinder 11 itself and a short-circuit current generated along the broken line D in the figure. The sucrose that is passed between the heating tubes 10 and 11 from inside the hopper 13 along the threaded groove 12 is heated and melted by the generation of heat, and falls toward the outlet 22.

Note that the threaded groove 12 on the outer periphery of the inner heating cylinder 10 prevents the so-called shot pass in which granular sucrose directly falls downward, and also controls the flow rate of sucrose and increases the heat transfer area. The granulated sucrose is melted into a thin film by easy heat exchange with the sucrose, and is then removed from the outlet 22 while stirring.
descended to.

Furthermore, the magnetic flux guide 20, coil support tube 19, and inner tube 14 are also affected by the generation of the alternating magnetic flux described above, and these have notches 20a, 19a, and 14a.
is formed, so no circumferential short-circuit current occurs and therefore no Joule heat is generated, but heat is generated due to hysteresis loss. However, the heat generated is smaller than that of Joule heat, and does not adversely affect the coil or other parts.

The temperature of the inner heating cylinder 10 is controlled by detecting the temperature with a temperature sensor 23 embedded in the cylinder 10 and adjusting the power applied to the inner excitation coil 17 according to the temperature. The lead wire 23a is led out through the center of the support shaft 15.

The temperature of the outer heating cylinder 11 is controlled by a temperature sensor 24 provided corresponding to each outer excitation coil 18.
The temperature of each part is detected and the applied power is adjusted according to the temperature to maintain the required temperature.

The sucrose melting device of the present invention is configured as described above,
Compared to a device with a buried nichrome wire heater, it takes a shorter time to reach the desired temperature. That is, since the device is heated by the heat transfer effect of the nichrome wire heater, it takes time to raise the temperature, whereas in the device according to the present invention, the inner heating tube and the outer heating tube themselves generate heat due to Joule heat and hysteresis loss. Since the outside of the outer excitation coil is covered with a magnetic flux guide made of magnetic material, a closed magnetic circuit is reliably formed by each magnetic flux guide and the outer heating cylinder, and even if only one heating cylinder is used, In comparison, the desired temperature is raised within a very short time without discoloring the sucrose. In addition, since the inner heating cylinder and the outer heating cylinder are made of magnetic materials such as silicon steel or iron, the internal electrical resistance of the magnetic material as an inductive load at room temperature or low temperature is small, and at the initial stage of temperature rise, there is a commensurately large resistance. By inducing a short circuit current, the amount of heat generated transiently reaches a maximum, and due to the resistance coefficients of the magnetic materials of the inner and outer heating cylinders, the current gradually decreases to the rated current as the temperature rises, so the desired current can be achieved in an extremely short period of time. temperature rises to . In addition, in devices with embedded nichrome wire heaters, the heating parts, that is, the inner heating cylinder and the outer heating cylinder, have thick walls, and it is necessary to use copper or aluminum materials with good thermal conductivity.
Material costs will increase.

On the other hand, the device according to the present invention can be made of any magnetic material regardless of thermal conductivity, and since the nichrome wire heater is not embedded, the inner heating cylinder and the outer heating cylinder can be made thin.
It becomes possible to increase the density of the magnetic flux passing through them, and the temperature rises to the desired temperature faster. Furthermore, the inner heating tube and the outer heating tube, which are made of magnetic materials, are themselves heat generating elements, and electrical energy can be saved by about 20% compared to heating with a nichrome wire heater. Furthermore, when heating the device with a nichrome wire heater, the nichrome wire heater, which is less flexible than ordinary electric wire, must be buried in the inner heating cylinder and the outer heating cylinder, respectively, as shown in Fig. 1. It takes time and effort to bury it, and it is necessary to install it with sufficient consideration for electrical insulation to prevent disconnection accidents. However, the device according to the present invention does not require complicated embedding processing, and the excitation coil is surrounded by an inner heating tube and an outer heating tube using electric wires that are more flexible than nichrome wire heaters, so processing is easier. be.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a sucrose melting device using a conventional nichrome wire heater, Fig. 2 is a cross-sectional view of a sucrose melting device according to the present invention, and Fig. 3 is a cross-sectional view of a sucrose melting device using a conventional nichrome wire heater.
4 is a sectional view taken along the line -- in FIG. 2. 10...Inner heating cylinder, 11...Outer heating cylinder, 1
2... Thread groove, 13... Hopper, 15... Support shaft, 17... Inner excitation coil, 18... Outer excitation coil.

Claims (1)

[Claims] 1.Equipped with an inner heating cylinder that has a thread groove on its outer peripheral surface and is rotatably supported, and an outer heating cylinder that is provided on the outer surface of the inner heating cylinder in a concentric arrangement, and a hopper is provided at the upper end between the two heating cylinders. In the sucrose melting device, in which sucrose can be freely inserted between the two heating cylinders from the hopper, the inner heating cylinder and the outer heating cylinder are formed of a magnetic material such as silicon steel or iron material, and the inner heating cylinder is made of a magnetic material such as silicon steel or iron. A coil support cylinder is provided concentrically on the center side of the cylinder, an inner excitation coil is provided on the outer periphery of the coil support cylinder, a plurality of outer excitation coils are provided on the outer periphery of the outer heating cylinder at positions shifted in the axial direction, and The outer sides of the plurality of outer excitation coils are covered with magnetic flux guides made of a magnetic material, and each of the magnetic flux guides and the coil support cylinder is formed with a continuous notch along the axial direction at a part of the circumferential direction, A sucrose melting device characterized in that an alternating current power source can be freely connected to each of the excitation coils, and when the power source is applied, an alternating magnetic flux is passed through the heating cylinders to generate heat.