JPS6215793A - Flexible heater - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a flexible heater using a pressure-sensitive resistor whose resistance value changes depending on pressure, and is used by being wrapped around an object to be heated. The amount of heating can be adjusted by adjusting the force and changing the resistance value.

[Conventional technology]

A conventional flexible heater is made of a nichrome resistance wire insulated and wrapped around an object to be heated, and the resistance wire is energized to generate Joule heat to heat the object.

[Problem that the invention seeks to solve]

However, in the conventional flexible heater described above, since the resistance value is constant, there is a problem that the amount of heating cannot be adjusted unless the applied voltage is changed.

Providing a voltage regulator would be large, expensive, and difficult to handle, so it is common to directly apply voltage from a commercial power supply or DC power supply.

Therefore, the object to be heated is heated at a constant amount of heat, so if, for example, when heating molten resin, moderate heating can be achieved in the summer, there will be insufficient heating in the winter, and vice versa. , energy saving and high efficiency heating are not possible.

In addition, in order to heat the object to be heated at an appropriate temperature, it is necessary to manufacture a large number of devices with resistance values suitable for the object.

[Summary of the Invention] In order to solve the above problems, the flexible heater 6 of the present invention has the following features:
As shown in the first diagram, a pressure sensitive resistor 2 is provided concentrically around the outer periphery of an elongated central conductor 1, an outer conductor 3 is provided concentrically around the outer periphery of this pressure sensitive resistor 2, and the outer periphery of this outer conductor 3 is insulated. It has a structure in which it is covered with a material 4.

The flexible heater 6 of the present invention is used by wrapping it around an object to be heated 7 and applying a voltage between the center conductor 1 and the outer conductor 3 as shown in the second figure. The pressure applied to each part of the pressure-sensitive resistor 2 changes uniformly, and the heated object 7
The amount of heating can be adjusted for eight cycles in total.

In this case, winding can be done by partially changing the force on the heated object 7.
You can also heat it by partially adjusting the heat.

[Detailed description of the invention]

FIGS. 1(a) and 1(b) are perspective views showing a first embodiment of the flexible heater of the present invention.

First, the configuration of the first embodiment will be explained.

In FIG. 1, 1 is an elongated central conductor made of metal such as copper or aluminum. A pressure sensitive resistor 2 is provided concentrically around the outer periphery of the center conductor 1.

The pressure-sensitive resistor 2 can be made of a material such as plastic or rubber with the addition of electrical materials such as metal powder, metal flakes, metal fibers, carbon powder, or carbon fiber, and is inversely proportional to the pressure. The resistance value changes accordingly.

Reference numeral 3 denotes an outer conductor provided concentrically around the outer periphery of the pressure-sensitive resistor 2, and is made of metal such as copper or aluminum. The outer periphery of the outer conductor 3 is covered with an insulating material 4 such as plastic.

Although FIG. 1 (al) shows an example of a round shape and FIG. 1(b) shows an example of a square shape, the shape can be determined as appropriate in the present invention.

Next, the operation of the first embodiment will be explained.

This flexible heater 6 is used by winding it around an object to be heated, for example, a molten resin conduit 7, at no intervals, as shown in the second diagram, and applying a voltage, for example, from a commercial power source, between the center conductor 1 and the outer conductor 3. . In this case, avoid wrapping around the valve 8.

When winding is done with force, the resistance value of the pressure-sensitive resistor 2 decreases in inverse proportion to the force, and the wound pressure-sensitive resistor 2 generates heat and melts the resin. pipe 7
is heated, and the molten resin 9 is sent in a molten state. The portion of the heater 6 that avoids the pulp 8 portion does not generate heat because no pressure is applied thereto.

Since a large pressure is applied to the heater portion 6a (referred to as the contact-side heater portion) that comes into contact with the pipe 7, the resistance value of the pressure-sensitive resistor 2 in this part decreases significantly and generates heat, which increases the heating of the pipe 7. heater portion 6b that contributes but does not come into contact with the pipe 7
Since almost no pressure is applied to this part (referred to as the non-contact side heater part), the resistance value of the pressure sensitive resistor 2 in this part hardly decreases and no heat is generated.

In other words, the non-contact side heater portion 6b fulfills the role of heat retention.

FIG. 3 shows an equivalent circuit diagram of the first embodiment in use. ■ is the power supply voltage applied between the center conductor 1 and the outer conductor 3, RV, , RV,... are the resistance values of each part of the pressure-sensitive resistor 2, and the winding is done with force to ensure uniform winding. When is l? VI#RVZ #...--#RVfi=RV, and its calorific value (Joule heat) is V''/RV.

By adjusting the winding force as a whole, the pressure applied to each part of the pressure-sensitive resistor 2 changes uniformly, and the amount of heating of the molten resin conduit 7 can be adjusted as a whole.

In addition, if the winding force is partially changed, the pressure applied to each part of the pressure-sensitive resistor 2 will change, and the amount of heat generated at each part will be V2/R.
V l, V"/RVZ, ...-, V"/
RVfi, and the amount of heating of the molten resin pipe 7 can be partially adjusted.

FIG. 4 is a perspective view showing a second embodiment. In this second embodiment, if the winding force is extremely strong, the resistance value of the pressure-sensitive resistor 2 will decrease too much and burnout can be prevented. Therefore, a protective resistor 5 is inserted between the center conductor l and the pressure sensitive resistor 2.

The equivalent circuit in use of this second embodiment is as shown in Figure 5, and the resistance values of each part of the protective resistor 5 are equal.
C,=RC,=...=RC,l. The heat generation amount of each part is V2/(1?Vl+RC1), V2/(
RVz+RC2)・・・・−.

V2/(RV11+RCll).

As described above, according to the present invention, the winding is configured using the pressure-sensitive resistor 2 whose resistance value changes depending on the force. Resistance values of each part of body 2 RV2...
can be changed uniformly or partially, and the amount of heating of the object to be heated 7 can be adjusted entirely or partially.

Therefore, when heating the molten resin 9, it is necessary to heat the molten resin 9 during the summer.

Overheating or underheating caused by seasonal temperature differences in winter can be countered by adjusting the wrapping force, and only the contact side heater portion 6a contributes to heating, and the non-contact side heater portion 6b plays the role of heat retention. This enables energy saving and highly efficient heating.

Furthermore, since the amount of heating can be adjusted by changing the wrapping force, the object to be heated can be heated at an appropriate temperature, and there is no need to manufacture a large number of devices with resistance values that match the heating temperature of the object to be heated.

[Brief explanation of the drawing]

FIG. 1 (al, (bl) is the first flexible heater of the present invention.
FIG. 2 is a sectional view showing an example of the usage state, FIG. 3 is an equivalent circuit diagram similarly in the usage state, FIG. 4 is a perspective view showing the second embodiment, and FIG. 5 is a perspective view showing the second embodiment. The figure is an equivalent circuit diagram in its usage state. 1... Center conductor, 2... Pressure sensitive resistor,
3... Outer conductor, 4... Insulating material, 5...
...Protective resistor, 6...Flexible heater of the present invention. Answer 1 (a,) (b) Answer 2 3 bunches of sticky notes

Claims (1)

[Claims] A flexible heater in which a pressure-sensitive resistor is provided concentrically around the outer periphery of an elongated central conductor, an outer conductor is provided concentrically around the outer periphery of the pressure-sensitive resistor, and the outer periphery of the outer conductor is covered with an insulating material.