JPH0433039Y2 - - Google Patents

Description

[Detailed explanation of the invention] [Subject of the invention] The invention relates to a heated toilet seat.More specifically, conductive metal short fibers, which are heat generating elements, are mixed into a resin molding material, and when energized, the resistance value changes depending on the temperature. This is a heated toilet seat made of a controlled heating element that has a positive temperature coefficient that increases as the toilet rises.

[Prior art]

The conventional heated toilet seat according to the present invention is used as a heated toilet seat by molding the toilet seat body, attaching a heating element made of nichrome wire and aluminum foil to the back of the toilet seat, and fixing the back cover of the toilet seat. Ta.

If this is shown in Fig. 1, 10 is a conventional heated toilet seat, 11 is a lid, 12 is a toilet seat body, 13 is a control box, 14 is a surface of the toilet seat body, 15 is a back cover of the toilet seat body, and 16 is a heater. , the heater 16 is attached to the back side of the toilet seat body 14.

[Problems with conventional technology and its technical analysis]

Regarding the conventional heated toilet seat, the toilet seat body 1
4. There are many parts such as the back cover 15 and heater 16, and labor is required to install the heater and secure the back cover.In particular, when handling the heater, the operator must be careful not to break the wire and prevent the terminal from loosening. However, there is a problem in that the work must be done with considerable attention.

[Technical Issues]

Therefore, the technical object of the present invention is to create a heated toilet seat that has a small number of parts and is easy to assemble.

[Technical means]

The technical measures taken to solve the above technical problems were to use a crystalline thermoplastic resin as a heating element for a heated toilet seat, with an average diameter of 40 to 120 μm and a length of 1 to 5 mm.
The heating element has a PTC characteristic in which the resistance value increases rapidly as the temperature rises when the temperature reaches a certain temperature range by mixing 10 to 40 VOL% of conductive short metal fibers, and the heating element is attached to the toilet seat body. This is a heated toilet seat with a controlled surface heating element, which has a central layer and synthetic resin placed on both sides of the heating element to form the surface layer.

[Effect of technical means]

The above technical means works as follows. In other words, a composite composition formed by mixing a thermoplastic resin and conductive short fibers has a property that when a certain temperature range is reached by energization, its resistance value rapidly increases as the temperature rises, that is, it has a positive temperature coefficient (hereinafter referred to as "positive temperature coefficient"). , PTC characteristics). Regarding this, please refer to Japanese Patent Application No. 58-71648 (Japanese Patent Application No. 59-196334)
It is disclosed in the publication "Composite composition with positive temperature coefficient".

In other words, when the conductive substance mixed with the thermoplastic resin is in the form of short fibers, the resistivity at the transition temperature rises rapidly even if the initial resistance value is small, and the range of change is large, that is, the resistance ratio increases. A heating element is formed from a composite composition that is extremely large and has a positive temperature coefficient where the PTC curves match when the temperature is raised and when the temperature is lowered, causing no hysteresis curve and no decrease in resistance value in the high temperature region. can.

When the temperature of the thermoplastic resin rises from room temperature and reaches a transition temperature, it changes from crystalline to amorphous, and due to the rapid increase in volume, the conductive path chains of the conductive short fibers contained in the resin are cut or By increasing the distance between the short fibers, the resistivity can be rapidly changed at a desired temperature.

In addition, in order to obtain stable PTC characteristics, the mixing ratio of conductive short fibers to the thermoplastic resin is preferably 10 to 40 VOL%. If the conductive short fibers are below this range, the conductivity will decrease too much. Moreover, if it exceeds this range, the conductive path chain will be difficult to break and the PTC will decrease.

[Special effects produced by the present invention]

The present invention produces the following unique effects. In other words, (1) the manufacturing process for the toilet seat body for a heated toilet seat can be shortened by just one injection molding process, reducing the manufacturing cost of the heated toilet seat; (2) the assembly process for the toilet seat body, heater, back cover, etc. It is suitable for mass production because it eliminates the need for erroneous assembly, and there is no shortage of parts, resulting in stable quality.

(3) The heating element placed in the center of the toilet seat is made of thermoplastic resin mixed with conductive fibers.
It has characteristics. Therefore, when the heating element exceeds a certain temperature, it will no longer generate heat when energized, and the temperature of the toilet seat can be maintained at an appropriate temperature without the need for a thermostat. As a result, the number of parts can be reduced.

(4) Thermostats require consideration of safety in the event of contact failure, but the heating element used in the toilet seat of this invention naturally adjusts the temperature due to its PTC characteristics. It has excellent reliability and can reliably adjust the temperature.

〔Example〕

Hereinafter, an example showing a specific example of the above technical means will be described.

(Example 1) 1 is the toilet seat body of a heated toilet seat, and 2 shown with diagonal lines is
This heating element is made by filling aluminum alloy fibers with a diameter of 90 μm and a length of 3 mm with 20 VOL% of ethylene vinyl acetate (EVA) copolymer.It has a volume resistivity of approximately 5 Ωcm and is approximately 2 mm thick. This is the part that generates heat.

The heating element 2 made of conductive short metal fibers and the thermoplastic resin is used as the center layer, and ABS resin is used as the skin material on both sides. Using a multi-material injection molding machine as shown in FIG. 3 is an insulating material, and 4 and 5 are electrodes embedded in the toilet seat body 2.

The resistance between the electrodes 4 and 5 measured with an electrometer is about 250Ω, and the power density of this heating element is 0.11w/cm ² (at room temperature), which is about 38°C.
It has the ability to raise the temperature. This material has PTC characteristics with a transition temperature (temperature at which resistance suddenly rises) of 50°C, and when the temperature exceeds 50°C, it no longer generates heat when energized. As a result, the pattern of the toilet seat surface temperature when changing the outside temperature is that when the temperature is controlled at a material standard of 50℃, and when the temperature does not exceed this transition temperature, a normal temperature increase that does not exhibit PTC characteristics occurs. be.

(Example 2) In Example-1, the EVA copolymer was
A heating element was formed by filling 20 VOL% of aluminum alloy fibers with a length of 60 μm and a length of 3 mm. The volume resistivity of heating element 1 was 10 Ωcm, the thickness of the heating element was 4 mm, and Example 1
The resistance between the electrodes is approximately 250Ω.
It is.

Next, the relationship between the voltage V between the electrodes 4 and 5 of the toilet seat body and the temperature T of the surface of the toilet seat body is shown in FIG.
As shown in , the temperature of the surface of the toilet seat body increases as the voltage increases.

Figure 3 A shows the temperature t and volume resistivity R of the heating element.
It is expressed as log, Example-1 is shown as B, Example-2 is shown as C, and when the resin is the same,
PTC is the same, and indicates a state in which the resistance value increases rapidly at approximately 50°C.

[Brief explanation of the drawing]

Figure 1 shows a conventional example of the present invention, where A is a perspective view;
B is a sectional view taken along line AA in A. Figure 2 shows this embodiment, where A is a plan view and B is a sectional view taken along line B-B of A.
C is an enlarged view of part of A. FIG. 3 is a graph of the example, in which A is a graph showing the relationship between voltage and surface temperature, and B is a graph showing the relationship between heating element and volume resistivity. 1... Toilet seat body, 1a, 1b... Epidermal layer, 2...
...heating element, 3...insulating section, 4, 5...electrode.

Claims (1)

[Scope of utility model registration request] As a heating element for a heated toilet seat, conductive metal short fibers with an average diameter of 40 to 120 μm and a length of 1 to 5 mm are mixed in a crystalline thermoplastic resin at 10 to 40 VOL%, and when a certain temperature range is reached by applying electricity, A heating element having PTC characteristics whose resistance value increases rapidly as the temperature rises, the heating element being a central layer of the toilet seat body,
A controlled surface heating toilet seat with synthetic resin placed on both sides of the heating element as a surface layer.