JP6987601B2 - Induction heating device - Google Patents

Description

The present invention relates to a device for inducing and heating a cylindrical object to be heated.

Generally, an electrophotographic photosensitive member (hereinafter, also referred to as a photosensitive drum) mounted on an electrophotographic apparatus has a photosensitive layer formed on a cylindrical metal base layer. Further, there is known a method of improving the durability of a photosensitive drum by forming a protective layer on the surface of the photosensitive layer and curing the protective layer by electron beam irradiation and heating. At this time, for the purpose of reducing the variation in hardness of the protective layer, there is a demand for a heating device capable of uniformly heating the photosensitive drum.

Methods using hot air heating, light heating, and induction heating have been attempted to heat the photosensitive drum. In particular, a method using induction heating is effective because it can be heated in a short time. Induction heating is a heating method in which an eddy current is generated near the surface of a conductive material when a magnetic field changes across the conductive material, and the Joule heat generated to heat the object to be heated. At this time, the eddy current flowing through the conductive material generates a magnetic field that hinders the change in the magnetic field. Induction heating has the characteristic that only the conductive material is heated, and if it is a non-conductive material, it is not heated even in the magnetic field generation region.

Further, the calorific value of the heated body differs depending on the relative magnetic permeability of the heated body. If the object to be heated is a material (ferromagnetic material) having a high relative permeability such as iron or nickel, a large amount of eddy current is generated even with a slight change in the magnetic field, and the calorific value increases. On the contrary, if the heated body is a material having a low relative magnetic permeability (non-magnetic material) such as aluminum or copper, the amount of eddy current generated is small and the calorific value is smaller than that of the ferromagnetic material. Further, the calorific value of the cylindrical heated body also differs depending on the outer diameter of the heated body. The larger the outer diameter of the object to be heated, the more eddy currents are generated and the larger the amount of heat generated.

A spiral-shaped induction heating coil is often used to heat a cylindrical heated object having a length such as a photosensitive drum. Further, when heating a plurality of types of heated objects having different lengths and diameters with a common induction heating coil, the magnetic field generation region generated by the induction heating coil and the length of the longest heated object match. It is common to use an induction heating coil. However, when the heated body having a short length is heated by using the above-mentioned induction heating coil, there is a problem that the end portion of the heated body generates heat excessively as compared with other parts. This is because eddy currents are generated at both the end of the heated body near the surface of the outer surface of the heated body and near the surface of the end surface of the heated body, so that the amount of heat generated at the end is larger than that of the other parts. This phenomenon is called the edge effect.

Patent Document 1 discloses a means for uniformly heating a heated body by using an induction heating coil having a magnetic field generation region longer than the length of the heated body. In Patent Document 1, a conductive auxiliary base material that generates heat by induction heating is placed at the end of the heated body to reduce the magnetic flux density near the end of the heated body and prevent excessive heat generation at the end. is doing. Further, the temperature of the end portion of the heated body can be finely adjusted by finely moving the distance between the auxiliary base material and the heated body.

Japanese Unexamined Patent Publication No. 2005-63753

The induction heating device described in Patent Document 1 has a problem that temperature unevenness occurs in the heated body when the outer diameter of the conductive auxiliary base material and the outer diameter of the heated body are different. When the outer diameter of the auxiliary base material is larger than the outer diameter of the heated body, more eddy currents flow through the auxiliary base material than the heated body, and the magnetic flux density near the end of the heated body becomes too small. As a result, the temperature of the end portion of the object to be heated becomes low. On the other hand, when the outer diameter of the auxiliary base material is smaller than the outer diameter of the heated body, the magnetic flux density in the vicinity of the end portion of the heated body becomes too large, and the temperature of the end portion of the heated body becomes high.
The present invention has been made in view of the above problems, and even when the outer diameter of the conductive auxiliary base material and the outer diameter of the object to be heated are different, the induction heating coil and the gripping mechanism are not replaced. It is an object of the present invention to provide an induction heating device capable of uniformly heating an object to be heated.

In order to achieve the above object, according to one aspect of the present invention,
An induction heating device including an induction heating coil in which a cylindrical object to be heated is arranged inside, and an auxiliary base material which is arranged inside the induction heating coil and generates eddy current by the induction heating coil to generate heat. And,
When the heated body is arranged inside the induction heating coil, a gripping member that is interposed between the heated body and the auxiliary base material to support the heated body is further provided.
The grip member is
At least the contact portion with the heated body is made of a non-conductive material.
The induction heating device is
The first heated body and the second heated body having an outer diameter larger than that of the first heated body can be selectively supported and supported.
The distance between one end of the first heated body and the auxiliary base material when the first heated body is arranged inside the induction heating coil is the distance between the second heated body and the induction heating body. Provided is an induction heating device that supports the heated body so as to be longer than the distance between one end of the second heated body and the auxiliary base material when placed inside the coil. ..

Further, according to another aspect of the present invention.
An induction heating device including an induction heating coil in which a cylindrical object to be heated is arranged inside, and an auxiliary base material which is arranged inside the induction heating coil and generates eddy current by the induction heating coil to generate heat. And,
When the heated body is arranged inside the induction heating coil, a grip member that supports the heated body and a gripping member that supports the heated body.
Further provided with a position adjusting means for adjusting the position of the auxiliary base material with respect to the gripping member.
The gripping member has at least a contact portion with the heated body made of a non-conductive material.
The induction heating device can selectively support the first heated body and the second heated body having an outer diameter larger than that of the first heated body, and the position adjustment thereof. The means is
The distance between one end of the first heated body and the auxiliary base material when the first heated body is arranged inside the induction heating coil is the distance between the second heated body and the induction heating body. An induction heating device that adjusts the position of the auxiliary base material with respect to the gripping member so as to be longer than the distance between one end of the second heated body and the auxiliary base material when placed inside the coil. Is provided.

According to the present invention, even when the outer diameter of the conductive auxiliary base material and the outer diameter of the heated body are different, the heated body is not replaced with an induction heating coil, an auxiliary base material, or a gripping mechanism. It becomes possible to provide an induction heating device capable of uniformly heating.

It is a figure which shows the apparatus outline of the induction heating apparatus of this invention. It is a schematic diagram for demonstrating the principle of this invention. It is sectional drawing of the gripping member which concerns on Example 1 of this invention. It is a figure of the gripping member which concerns on Example 2 of this invention, (a) is a sectional view, (b) is a bottom view. It is a figure which shows the outline of the structure of the induction heating apparatus which concerns on Example 3 of this invention. It is a figure which shows the outline of the structure of the induction heating apparatus which concerns on the prior art.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the present invention is not limited to the following embodiments.
FIG. 1 is a diagram showing an outline of the induction heating device of the present invention.

The spiral-shaped induction heating coil 100 is fixed by a coil support member 101 and attached to a pedestal 102. The induction heating coil 100 is connected to the high frequency power supply 104 via the matching machine 103. The high-frequency power supply 104 is connected to the control unit 115, and a high-frequency current corresponding to an output command from the control unit 115 is passed through the induction heating coil 100 to heat the heated body 120 arranged inside the induction heating coil. Can be done.

The auxiliary base materials 111a and 111b are held by the bearing portions 112a and 112b and attached to the elevating mechanism 114a and 114b.
The elevating mechanisms 114a and 114b are connected to the control unit 115 and can operate in response to a position movement command from the control unit.
When the heated body 120 is arranged inside the induction heating coil 100, the heated body 120 can be contact-held by sandwiching the heated body 120 between the gripping members 110a and 110b connected to the auxiliary base materials 111a and 111b. Is. The grip member 110a is interposed between the heated body 120 and the auxiliary base material 111a, and the gripping member 110b is interposed between the heated body 120 and the auxiliary base material 111b.

At least one of the gripping members 110a and 110b is connected to the rotation mechanism 113, and has a structure in which the gripped body 120 to be heated can be rotated. In the example shown in FIG. 1, the gripping member 110a is rotated by the rotation mechanism 113 together with the auxiliary base material 111a. Then, the heated body 120, the gripping member 110b, and the auxiliary base material 111b are rotated by the auxiliary base material 111a.
The rotation axes of the induction heating coil 100 and the heated body 120 can be adjusted substantially coaxially by an adjustment mechanism (not shown).

FIG. 2 is a schematic diagram for explaining the principle of the present invention.
The length of the induction heating coil 100 (L in FIG. 2) is within the range in which eddy currents are generated not only in the object to be heated 120 but also in the auxiliary base materials 111a and 111b by passing a high frequency current through the induction heating coil 100. The length.

The auxiliary base materials 111a and 111b are made of a conductive material. An eddy current flows through the auxiliary base materials 111a and 111b, and a magnetic field is generated in a direction that weakens the magnetic field generated by the induction heating coil 100 to adjust the magnetic flux density near the end of the heated body 120, resulting in excess of the end. It is possible to prevent excessive heat generation. The vicinity of the end portion of the heated body 120 means the vicinity of the upper end portion of the heated body 120 (near the end portion close to the gripping member 110a) and the vicinity of the lower end portion of the heated body 120 (near the end portion close to the gripping member 110b). Neighborhood).

The gripping members 110a and 110b are made of a non-conductive material at least in contact with the heated body 120. This is because it does not affect the magnetic field generated by the induction heating coil 100 and the auxiliary base materials 111a and 111b.

The auxiliary base materials 111a and 111b have a cylindrical or cylindrical shape and have an outer diameter equal to or larger than the outer diameter of the heated body 120. That is, the auxiliary base materials 111a and 111b of the induction heating device according to the present invention have an outer diameter equal to or larger than the outer diameter of the object to be heated having the maximum outer diameter. This is because the temperature of the end portion of the heated body 120 does not rise even when the heated body having the largest outer diameter among the heated bodies to be heated by using the induction heating device according to the present invention is heated. To make it.

The induction heating device has means for adjusting the distance between the auxiliary base materials 111a and 111b and one end of the heated body according to the outer diameter of the heated body 120. Using such adjusting means, the distance between the auxiliary base materials 111a and 111b and one end of the heated body is adjusted to the optimum value obtained for each outer diameter of the heated body by conducting a heating experiment in advance. The "distance between the auxiliary base materials 111a and 111b and one end of the heated body" means "the distance between the lower end of the auxiliary base material 111a and the upper end of the heated body" and "the upper end of the auxiliary base material 111b and the heated body". It means "distance from the bottom edge". When the outer diameter of the heated body 120 is smaller than the outer diameter of the auxiliary base materials 111a and 111b, the distance between the auxiliary base materials 111a and 111b and one end of the heated body 120 is increased so that the outer diameter is small. This is to prevent the temperature near the end from becoming low even when the heated body is heated.

As an example of means for adjusting the distance between the auxiliary base material and the heated body according to the outer diameter of the heated body, as shown in FIGS. 3 and 4, the cross-sectional shapes of the gripping members 110a and 110b are auxiliary groups. Examples thereof include a configuration in which the diameter is reduced as the distance from the materials 111a and 111b increases.
Both the gripping members shown in FIGS. 3 and 4 can support the first heated body and the second heated body having an outer diameter larger than that of the first heated body.
Further, the gripping members shown in FIGS. 3 and 4 are all gripped members.
The distance between one end of the first heated body and the auxiliary base material when the first heated body is placed inside the induction heating coil is set so that the second heated body is placed inside the induction heating coil. The heated body is supported so as to be longer than the distance between one end of the second heated body and the auxiliary base material at the time.
The numerical values shown in FIGS. 3 and 4 indicate the sizes when used in the examples described later, and these numerical values do not limit the technical scope of the present invention at all.

As for the gripping member as shown in FIG. 3, since it is not necessary to process the shape of the cross section of the gripping member step by step, the manufacturing of the gripping member becomes easy.
Further, the gripping member as shown in FIG. 4 can contact and grip a part of the end surface and the inner peripheral surface of the heated body, and can grip the heated body as compared with the gripping member as shown in FIG. The contact area with the member can be increased. Therefore, even if the gripping member is used repeatedly, the gripping member is less likely to wear. As a result, it is possible to suppress "variation in which the distance between one end of the object to be heated and the auxiliary base material is shortened" caused by the wear of the grip member.

As described above, the gripping member may also have a function of adjusting the "distance between one end of the heated body and the auxiliary base material", and as described below, another means independent of the gripping member is "covered". It may have a function of adjusting the distance between one end of the heating body and the auxiliary base material.
If another means independent of the grip member has the function of adjusting the "distance between one end of the object to be heated and the auxiliary base material", the induction heating device is used.
An induction heating coil in which a cylindrical object to be heated is placed inside,
An auxiliary base material that is placed inside the induction heating coil and generates eddy current by the induction heating coil to generate heat.
When the heated body is placed inside the induction heating coil, the gripping member that supports the heated body and
A position adjusting means for adjusting the position of the auxiliary base material with respect to the gripping member is provided.

At least the contact portion of the grip member with the heated body is made of a non-conductive material.
The induction heating device can support the first heated body and the second heated body having an outer diameter larger than that of the first heated body.
The position adjusting means adjusts the position of the auxiliary base material with respect to the gripping member as follows.
"The distance between one end of the first heated body and the auxiliary base material when the first heated body is placed inside the induction heating coil" is "the second heated body is inside the induction heating coil." It is longer than the distance between one end of the second heated body and the auxiliary base material when it is arranged.

An example of the induction heating device as described above will be described with reference to FIG.
The induction heating device shown in FIG. 5 has position adjusting means 130a and 130b for adjusting the positions of the ends of the auxiliary base materials 111a and 111b with respect to the positions of the gripping members 110a and 110b. In such a configuration, by adjusting the positions of the ends of the auxiliary base materials 111a and 111b with respect to the positions of the gripping members 110a and 110b according to the outer diameter of the heated body 120, the auxiliary base materials 111a and 111b and the auxiliary base materials 111a and 111b can be adjusted. The distance from one end of the heated body 120 can be adjusted.

The position adjusting means 130 shown in FIG. 5 may be any as long as the distance between the auxiliary base material and the gripping member can be adjusted. for example,
1) In the space below the dielectric superheat coil, the heated body is gripped by sandwiching the heated body from above and below by the gripping member.
2) While holding the heated body, raise the gripping members 110a and 110b so that the center of the heated body in the longitudinal direction and the center of the dielectric superheated coil in the longitudinal direction substantially coincide with each other. Raise,
3) After that, while maintaining the positions of the gripping members 110a and 110b, the auxiliary base material 111a is raised by a predetermined amount and the auxiliary base material 111b is lowered by a predetermined amount to form the gripping member and the auxiliary base material. And the distance between the object to be heated and the auxiliary base material are adjusted to a predetermined amount.
By using such a position adjusting means, the distance between one end of the heated body and the auxiliary base material can be adjusted regardless of the inner diameter of the heated body. That is, even if the thickness is changed in addition to the length and outer diameter of the heated body, the heated body can be uniformly heated without exchanging the induction heating coil or the gripping mechanism.

The induction heating device is
The outer diameter of the first heated body and the first distance are associated and accumulated,
It is preferable to further include a storage portion that stores the outer diameter of the second heated body in association with the second distance.
The outer diameter of the second heated body is larger than the outer diameter of the first heated body.
The first distance is longer than the second distance.

Then, when the first heated body is arranged inside the induction heating coil, the position adjusting means receives the first distance associated with the outer diameter of the first heated body from the accumulating portion. Then, the position of the auxiliary base material with respect to the gripping member is adjusted so that the distance between one end of the heated body and the auxiliary base material is the first distance.
Further, the position adjusting means receives a second distance associated with the outer diameter of the second heated body from the accumulating portion when the second heated body is arranged inside the induction heating coil. Then, the position of the auxiliary base material with respect to the gripping member is adjusted so that the distance between one end of the heated body and the auxiliary base material is the second distance.

The operator of the induction heating device may determine whether the heated body arranged inside the induction heating coil is the first heated body or the second heated body, and the outer diameter of the heated body is determined. An outer diameter measuring means for measuring may be further provided, and the determination may be made based on the value of the outer diameter of the heated body measured by the outer diameter measuring means.

In order to stably adjust the magnetic flux density in the vicinity of the end portion, it is preferable that the auxiliary base materials 111a and 111b are made of a material having a relative magnetic permeability similar to that of the heated body 120. When the auxiliary base materials 111a and 111b have a cylindrical shape, the thickness of the auxiliary base materials 111a and 111b is preferably 5 times or more the skin depth of the auxiliary base materials 111a and 111b. This "thickness of the auxiliary base material" is {(outer diameter of the auxiliary base material-inner diameter of the auxiliary base material) / 2}. Further, the "skin depth" is "the depth at which the electromagnetic field incident on a certain substance is attenuated to 1 / e (≈1 / 2.718)".

When the heated body 120 and the auxiliary base materials 111a and 111b are heated by induction heating, the grip members 110a and 110b are also heated by heat conduction. If the temperature of the gripping members 110a and 110b before heating fluctuates, the amount of heat transferred from the heated body 120 to the gripping members 110a and 110b fluctuates, which hinders uniform heating of the heated body 120. Therefore, it is preferable that the gripping members 110a and 110b or the auxiliary base materials 111a and 111b have a cooling mechanism and keep the temperature before heating constant.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples.
<Example 1>
A heating test was performed using the induction heating device shown in FIG.
Table 1 shows the outer diameter, inner diameter, and length of the heated body 120 used in this embodiment. As shown in Table 1, the heated body 120 used in this embodiment is three types of photosensitive drums having different outer diameters, inner diameters, and lengths.

The base layer of the heated body 120 is made of an aluminum alloy and has a relative magnetic permeability of about 1.0. A protective layer having a film thickness of about 5.0 μm is formed on the outermost layer of the heated body 120.

As the induction heating coil 100, a linear 8 mm copper tube bent into a spiral shape was used. The total length (L in FIG. 2) of the induction heating coil 100 was 450 mm, the outer diameter (D in FIG. 2) was 88 mm, and the number of turns was 23 turns. Cooling water was supplied to the inside of the copper tube to cool it. The induction heating coil 100 was fixed to a coil support member 101 composed of bakelite. The induction heating coil 100 was connected to the high frequency power supply 104 via the matching machine 103. Further, the temperature at the center position of the longitudinal portion of the heated body 120 is measured by a radiation thermometer (not shown), and the temperature is input to the control unit 115 to enable heating by feedback control.

The auxiliary base materials 111a and 111b are made of an aluminum alloy which is the same material as the base layer of the heated body 120, and have a cylindrical shape with an outer diameter of 30 mm. This is substantially the same as the outer diameter of the heated body 120 having the maximum outer diameter. Further, cooling water was supplied to the auxiliary base materials 111a and 111b to cool the auxiliary base materials 111a and 111b.

The gripping members 110a and 110b were made of PEEK (polyetheretherketone) and attached to the auxiliary base materials 111a and 111b. The contact portions of the gripping members 110a and 110b with the heated body 120 have a tapered shape that shrinks in diameter as the distance from the auxiliary base materials 111a and 111b is increased as shown in FIG. When the gripping members 110a and 110b contact and grip the heated body 120, the distance between one end of the heated body 120 and the auxiliary base materials 111a and 111b is set to the value shown in Table 1 obtained by conducting a heating experiment in advance. .. Further, the gripping members 110a and 110b were cooled by heat conduction from the cooling auxiliary base materials 111a and 111b.

The auxiliary base materials 111a and 111b were held by the bearing portions 112a and 112b and attached to the elevating mechanism 114a and 114b. The elevating mechanisms 114a and 114b are composed of a single-axis robot and a controller, are connected to a control unit 115 configured by a PLC (programmable logic controller), and have position coordinates of each operation in response to a position movement command from the control unit 115. Made movable to. When arranging the heated body 120 inside the induction heating coil 100, the heated body 120 was contact-held by sandwiching the heated body 120 between the gripping members 110a and 110b connected to the auxiliary base materials 111a and 111b. .. Further, at least one of the gripping members 110a and 110b is connected to the rotation mechanism 113, and the gripped body 120 to be heated has a rotatable structure.

Next, the procedure of the heating experiment performed in Example 1 will be described.
First, the heated body 120 was placed above the gripping member 111b with the elevating mechanism 114b lowered. After that, the elevating mechanism 114a was lowered, and the heated body 120 was sandwiched between the gripping member 110a and the gripping member 110b from above and below to contact and grip the heated body 120. At this time, by providing a pressing mechanism (not shown) having a spring between the elevating mechanism 114a and the bearing portion 112a, even if the length of the heated body 120 varies, the gripping members 110a and 110b 10 the heated body 120. The structure is such that it can be sandwiched with a force of ~ 20N.

Next, by raising the elevating mechanisms 114a and 114b while the heated body 120 is sandwiched between the gripping member 110a and the gripping member 110b from above and below, the heated body 120 is induced and heated as shown in FIG. It was placed inside 100. At that time, the positions of the elevating mechanisms 114a and 114b were adjusted so that the center in the longitudinal direction of the body to be heated 120 and the center in the longitudinal direction of the induction heating coil 100 coincided with each other.

Next, the gripped body 120 was rotated at a rotation speed of about 100 rpm by the rotation mechanism 113. Since the gripping members 110a and 110b and the heated body 120 are pressed by a force of 10 to 20N, the gripping members 110a and 110b and the heated body 120 can rotate at the same speed without slipping. The reason why the heated body 120 is rotated during heating is to prevent temperature unevenness in the circumferential direction of the heated body.

Next, a high-frequency current was passed through the induction heating coil 100 by the high-frequency power supply 104 to heat the heated body 120. The heating control was feedback control, and the setting was such that heating could be performed in 10 seconds from the initial temperature of 23 ° C to the target temperature of 125 ° C. The lower part (position 10 mm above the lower end of the heated body 120), the central part (longitudinal center position of the heated body 120), and the upper part (position 10 mm below the upper end of the heated body 120) at the end of heating. ) Was measured and the temperature difference was evaluated. A thermoviewer was used for the measurement, and the temperature of the surface of the protective layer of the photosensitive drum was measured.

After the heating is completed, the rotation of the heated body 120 is stopped, and the elevating mechanism 114a and 114b are lowered while the heated body 120 is sandwiched between the gripping member 110a and the gripping member 110b from above and below to lower the heated body 120. It was moved to the outside of the induction heating coil 100. After that, the elevating mechanism 114b was not raised, only the elevating mechanism 114a was raised, the grip member 110a was separated from the upper end of the object to be heated 120, and the object to be heated 120 was removed from the grip member 110b.

Table 2 shows the results of measuring the temperature of the heated body after heating and heating under the above conditions. Excessive heat generation at the end of the heated body 120 can be suppressed in any of the heated bodies 120 having different outer diameters and lengths shown in Table 1, and the maximum temperature at the lower temperature, the central temperature, and the upper temperature can be suppressed. The temperature difference from the minimum temperature was also 2 ° C or less.

<Example 2>
The same heating test as in Example 1 was performed using the gripping members 110a and 110b having a shape in which the diameter is gradually reduced as the distance from the auxiliary base materials 111a and 111b is increased as shown in FIG. The conditions are the same as those in the first embodiment except for the gripping members 110a and 110b.
The gripping members 110a and 110b used in this embodiment have a structure that fits with the heated body 120. Then, when the heated body 120 is gripped by being sandwiched between the gripping member 110a and the gripping member 110b from above and below, the heated body 120 and the gripping members 110a and 110b can be substantially coaxial with each other.
Table 3 shows the results of measuring the temperature of the heated body after heating and heating under the above conditions. The same results as in Example 1 were obtained, and in any of the heated bodies 120 having different outer diameters and lengths shown in Table 1, excessive heat generation at the end of the heated body 120 could be suppressed, and the lower temperature was adjusted. The temperature difference between the maximum temperature and the minimum temperature at the central temperature and the upper temperature was also 2 ° C. or less.

<Example 3>
The same heating test as in Example 1 was performed using the induction heating device shown in FIG.
In the induction heating device shown in FIG. 5, the shape of the contact surface of the gripping members 110a and 110b with the heated body 120 is flat, and the thickness is 1.0 mm. The gripping members 110a and 110b were attached to the position adjusting means 130a and 130b, and the position adjusting means 130a and 130b were composed of a robo cylinder and a controller and connected to the control unit 115. Further, an information storage unit 210 was connected to the control unit 115, and the information storage unit 210 stored position movement information according to the outer diameter of the heated body 120 measured in advance. As a result, the control unit 115 issues a position movement command according to the outer diameter of the heated body 120 to the position adjusting means 130a and 130b, so that the distance between the auxiliary base materials 111a and 111b and one end of the heated body 120 is shown in Table 1. The position adjusting means 130a and 130b were made operable so as to have the value of.

The auxiliary base materials 111a and 111b were held by the bearing portions 112a and 112b and attached to the elevating mechanism 114a and 114b. The elevating mechanisms 114a and 114b are composed of a single-axis robot and a controller, are connected to the control unit 115, and can move to predetermined position coordinates at each operation in response to a position movement command from the control unit 115.
Both the Robo cylinder and the single-axis robot are high-precision electric actuators with a ball screw, linear guide and AC servo motor.

When arranging the heated body 120 inside the induction heating coil 100, the heated body 120 is brought into contact with the heated body 120 by sandwiching the heated body 120 from above and below with the gripping members 110a and 110b connected to the auxiliary base materials 111a and 111b. I grabbed it. Further, at least one of the gripping members 110a and 110b is connected to the rotation mechanism 113 and is rotated by the rotation mechanism 113. In the example shown in FIG. 5, the gripping member 110a is rotated by the rotation mechanism 113. Then, the heated body 120 and the gripping member 110b are rotated by the gripping member 110a.

Table 4 shows the results of measuring the temperature of the heated body after heating and heating under the above conditions. The same results as in Example 1 were obtained, and in any of the heated bodies 120 having different outer diameters and lengths shown in Table 1, excessive heat generation at the end of the heated body 120 could be suppressed, and the lower temperature was adjusted. The temperature difference between the maximum temperature and the minimum temperature at the central temperature and the upper temperature was also 2 ° C. or less.

<Comparison example>
Using the induction heating device shown in FIG. 6, the same heating test as in Example 1 was performed.
In the induction heating device shown in FIG. 6, the shape of the contact surface of the gripping members 110a and 110b with the heated body 120 is flat, and the thickness is 1.0 mm. Then, regardless of the outer diameter of the heated body 120, heating was performed with the distance between one end of the heated body 120 and the auxiliary base materials 111a and 111b being 1.0 mm. The conditions were the same as in Example 1 except for the gripping members 110a and 110b.

Table 5 shows the results of measuring the temperature of the heated body after heating and heating under the above conditions. In the heated body 120 having an outer diameter of 30 mm, the outer diameters of the auxiliary base materials 111a and 111b of 30 mm and the outer diameter of the heated body 120 are substantially the same. Therefore, excessive heat generation at the end portion of the heated body 120 can be suppressed, and the temperature difference between the maximum temperature and the minimum temperature at the lower temperature, the central temperature, and the upper temperature is 2 ° C. or less.

However, in the heated body 120 having an outer diameter of 24 mm in which the outer diameter of the heated body 120 is smaller than the outer diameters of the auxiliary base materials 111a and 111b, the temperature difference between the lower temperature and the upper temperature was 1 ° C. Was 20 ° C lower than the central temperature. It is considered that this is because more eddy currents flowed through the auxiliary base materials 111a and 111b than the heated body 120, and the magnetic flux density near the end of the heated body 120 became too small.
Further, in the heated body 120 having an outer diameter of 20 mm in which the outer diameter of the heated body 120 is smaller than the outer diameters of the auxiliary base materials 111a and 111b, the temperature difference between the lower temperature and the upper temperature was 1 ° C. The temperature was 26 ° C lower than the central temperature. It is considered that this is also because more eddy currents flowed through the auxiliary base materials 111a and 111b than the heated body 120, and the magnetic flux density near the end of the heated body 120 became too small.

100 Induction heating coil 101 Coil support member 102 Coil pedestal 103 Matching device 104 High frequency power supply 110 Grip member 111 Auxiliary base material 112 Bearing part 113 Rotation mechanism 114 Elevating mechanism 115 Control part 120 Heated object 130 Position adjusting means 210 Information storage part

Claims (6)

An induction heating device including an induction heating coil in which a cylindrical object to be heated is arranged inside, and an auxiliary base material which is arranged inside the induction heating coil and generates eddy current by the induction heating coil to generate heat. And,
When the heated body is arranged inside the induction heating coil, a gripping member that is interposed between the heated body and the auxiliary base material to support the heated body is further provided.
The grip member is
At least the contact portion with the heated body is made of a non-conductive material.
The induction heating device is
The first heated body and the second heated body having an outer diameter larger than that of the first heated body can be selectively supported and supported.
The distance between one end of the first heated body and the auxiliary base material when the first heated body is arranged inside the induction heating coil is the distance between the second heated body and the induction heating body. Induction heating is characterized in that it supports the heated body so as to be longer than the distance between one end of the second heated body and the auxiliary base material when it is arranged inside the coil. Device. The induction heating device according to claim 1, wherein the grip member has a tapered shape whose cross-sectional shape shrinks as the distance from the auxiliary base material increases. The induction heating device according to claim 1, wherein the grip member has a shape in which the cross-sectional shape gradually decreases in diameter as the distance from the auxiliary base material increases. An induction heating device including an induction heating coil in which a cylindrical object to be heated is arranged inside, and an auxiliary base material which is arranged inside the induction heating coil and generates eddy current by the induction heating coil to generate heat. And,
When the heated body is arranged inside the induction heating coil, a grip member that supports the heated body and a gripping member that supports the heated body.
Further provided with a position adjusting means for adjusting the position of the auxiliary base material with respect to the gripping member.
The gripping member has at least a contact portion with the heated body made of a non-conductive material.
The induction heating device can selectively support the first heated body and the second heated body having an outer diameter larger than that of the first heated body, and the position adjustment thereof. The means is
The distance between one end of the first heated body and the auxiliary base material when the first heated body is arranged inside the induction heating coil is the distance between the second heated body and the induction heating body. It is characterized in that the position of the auxiliary base material with respect to the gripping member is adjusted so as to be longer than the distance between one end of the second heated body and the auxiliary base material when placed inside the coil. Induction heating device. The outer diameter of the first heated body and the first distance are associated and accumulated.
Further provided with a storage portion for accumulating the outer diameter of the second heated body in association with the second distance.
The first distance is longer than the second distance,
The position adjusting means is
When the first heated body is arranged inside the induction heating coil, the gripping member is set so that the distance between one end of the heated body and the auxiliary base material is the first distance. Adjust the position of the auxiliary substrate with respect to
When the second heated body is arranged inside the induction heating coil, the gripping member is set so that the distance between one end of the heated body and the auxiliary base material is the second distance. The induction heating device according to claim 4, wherein the position of the auxiliary base material is adjusted with respect to the relative base material. Further equipped with an outer diameter measuring means for measuring the outer diameter of the object to be heated,
In the position adjusting means, the distance between one end of the heated body and the auxiliary base material is accumulated in the storage portion in association with the value of the outer diameter of the heated body measured by the outer diameter measuring means. The induction heating device according to claim 5, wherein the position of the auxiliary base material with respect to the gripping member is adjusted so as to be a first distance or a second distance.

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