KR200494267Y1 - Safety learning aids to experiment with heat transfer in gas - Google Patents

Abstract

A safety learning tool for experimenting with heat transfer in a gas is disclosed.
The present invention disclosed is an upper opening-type lower case having an intake hole for inhaling external air; a PTC heating element that is built into the lower case so as not to block the intake hole and generates heat by connecting a power source; a lower opening-type upper case coupled to the upper portion of the lower case and having an exhaust hole through which air heated by the PTC heating element is exhausted; and a plastic bag fixed by hanging on the upper case, with an opening facing the exhaust hole of the upper case, and having a thermochromic sticker attached to the surface that changes color depending on the air temperature or painted with oil-based zion paint. .

Description

Safety learning aids to experiment with heat transfer in gas

This invention relates to a teaching aid used for science learning of elementary school students.

In more detail, it is intended to test the transfer of heat in the gas, and it provides safety and safety and It relates to a safety learning tool for testing the transfer of heat in a gas that is easy to move and store.

There is a unit called 'Transfer of Heat in Gases' in a science subject in the 5th grade of elementary school.

The above section is to observe the convection phenomenon in liquid or gas and to learn the movement of heat in the convection phenomenon through experimentation, and two types of experimental methods are generally used.

The first experimental method is to visually confirm that the hot air rises upward by convection by blowing the soap bubbles upwards while the alcohol lamp is lit. It is a possible experimental method.

In the second test method, a safety cylinder is installed on the crater of a portable gas stove, and the opening part of a plastic bag that will serve as a hot air balloon is placed on the top of the safety cylinder to complete the preparation work, and then the plastic By heating the air in the bag and observing the movement of the plastic bag, it is an experimental method that can visually confirm that the hot air rises upward by convection phenomenon through the synergistic action of the plastic bag.

However, given that the above-mentioned conventional experimental methods have a risk of safety accidents due to the use of direct fire devices such as alcohol lamps or portable gas stoves, even though the learning target is elementary school students, learning teaching aids using safer heat sources needs to be proposed.

Document 1: Registered Utility Model Publication No. 0340925 Document 2: Public Utility Model Publication No. 2009-0006059

The purpose of the present invention is to improve safety and safety by producing a finished product in which a PTC heating element that uses electricity is applied instead of a direct fire means such as an alcohol lamp or a portable gas stove, which has been used as a heating source for gas in the past to experiment with heat transfer in gas. It is to provide a safety learning tool for experimenting with the transfer of heat in a gas that is easy to move and store.

The technical problems to be achieved of the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by those of ordinary skill in the art to which the present invention belongs from the description below. There will be.

According to the above object, the present invention is a safety learning tool for experimenting with the movement of heat in a gas, an upper opening-type lower case having an intake hole for inhaling external air; a PTC heating element that is built into the lower case so as not to block the intake hole and generates heat by connecting to a power source; a lower opening-type upper case bound to the upper part of the lower case and having an exhaust hole for exhausting the heated air heat-exchanged at a high temperature by the PTC heating element; and an opening positioned on the exhaust hole so that the heated air discharged from the exhaust hole of the upper case flows into the inside, and a thermochromic sticker that changes color depending on the temperature of the introduced heating air is attached to the surface or oil-based Zion paint is applied. A safety learning tool for testing the transfer of heat in a gas containing a painted plastic bag is provided.

Preferably, a control module for turning on/off the PTC heating element or setting a temperature is provided on one side of the upper case, and a PTC heating element is provided inside the upper case by separating the installation space of the control module from other spaces. A heat shield that can block the heat generated from being transferred to the control module may be provided.

Preferably, a temperature sensor for detecting the temperature of the PTC heating element in real time and transmitting the sensed temperature data to the control module, wherein the control module includes a temperature value transmitted from the temperature sensor if the temperature value is greater than or equal to a set temperature It can be controlled so that the power to the heating element is cut off.

Preferably, the PTC heating element may be installed to be spaced apart from the intake hole by the brackets on both sides.

The present invention can improve safety by replacing the existing direct-fired heating source with a PTC heating element that generates heat by electricity.

In addition, the present invention can prevent burn accidents due to carelessness by sealing the PTC heating element in a safety case, and has an advantage in that it has a longer lifespan compared to the existing teaching aids as it is not easily broken by impact or falling.

In addition, the present invention is less affected by the wind than the direct-fired parish, so it can be tested in a relatively unfavorable external environment, and the experimental results are accurate and consistent.

The effect of the present invention is not limited to the above-described effect, and it should be understood to include all effects that can be inferred from the configuration of the invention described in the detailed description or claims of the present invention.

1 is an exploded perspective view of a safety learning tool for testing the movement of heat in a gas according to the present invention;
2 is a bottom perspective view of the upper case;
Figure 3 is a combined perspective view of Figure 1
4 is a cross-sectional view taken along line AA of FIG. 3
Figure 5a is a state diagram before the experiment
Figure 5b is a state diagram during the experiment, a state diagram in which hot air is injected into a plastic bag;
Figure 5c is a state diagram in which hot air is injected into the plastic bag and blown away by convection phenomenon;

Terms used in this specification will be briefly described, and the present invention will be described in detail.

The terms used in the present invention have been selected as currently widely used general terms as possible while considering the functions in the present invention, but this may vary depending on the intention or precedent of a person skilled in the art, the emergence of new technology, and the like. In addition, in a specific case, there is a term arbitrarily selected by the applicant, and in this case, the meaning will be described in detail in the description of the corresponding design. Therefore, the terms used in the present invention should be defined based on the meaning of the term and the overall contents of the present invention, rather than the name of a simple term.

In the entire specification, when a part "includes" a certain component, it means that other components may be further included, rather than excluding other components, unless otherwise stated. In addition, terms such as "unit" and "module" described in the specification mean a unit that processes at least one function or operation, which may be implemented as hardware or software, or a combination of hardware and software.

Hereinafter, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those of ordinary skill in the art to which the present invention pertains can easily implement it. However, the present invention may be implemented in several different forms and is not limited to the embodiments described herein. And in order to clearly explain the present invention in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are attached to similar parts throughout the specification.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

1 is an exploded perspective view of a safety learning tool for testing the movement of heat in a gas according to the present invention, Figure 2 is a bottom perspective view of the upper case, Figure 3 is a combined perspective view of Figure 1, Figure 4 is line AA of Figure 3 Cross-sectional view, Figure 5a is a state diagram before the experiment, Figure 5b is a state diagram during the experiment, a state diagram in which hot air is injected into the plastic bag.

Referring to the above drawings, the safety learning tool (hereinafter referred to as 'safety learning tool', 100) for experimenting with the movement of heat in the gas according to the present invention is for learning the convection phenomenon of the gas according to the movement of heat through the experiment. As a teaching aid with safety guaranteed by applying a heating element that is heated by electricity instead of a direct fire type, it may include a lower case 110 , a PTC heating element 120 , an upper case 130 , and a plastic bag 140 .

When the lower case 110 and the upper case 130 are combined with each other, they have a housing shape, and the PTC heating element 120 is sealed therein, thereby serving as a safety case.

The lower case 110 may be, for example, in the shape of an upper opening-type rectangular box, but the shape is not limited thereto.

A fastening hole 111 for screw fastening with the upper case 130 may be provided at an upper edge of the lower case 110 .

A draw-out hole 112 for drawing out the power line 121 of the PTC heating element 120 mounted therein may be provided in the lower case 110 .

The lower case 110 may be provided with a pair of winding protrusions 113 in the shape of a letter symmetrical to each other in order to wind the power wire 121 in the vicinity of the external draw-out hole 112 . This is useful when storing or transporting the safety learning aid 100 because it can be arranged by winding without drooping the power cord.

The lower case 110 may be made of a plastic material with low heat conduction, and a heat dissipation coating or a heat sink may be installed on the inner surface of the PTC heating element 120 to prevent heat from being conducted to the outside. This is to prevent unnecessary electricity consumption by blocking heat leakage to the outside, as well as to prevent burns during handling.

The PTC heating element 120 serves as a heating source for heating the gas. When the temperature becomes too high, the resistance increases together and the amount of current decreases to lower the temperature. When the temperature decreases, the resistance decreases and the amount of current increases. As a heating element on the principle that heat is started again after being turned on, it consumes less power and is safe because there is no risk of fire due to high temperature.

The PTC heating element 120 may be fixedly installed on the lower case 110 , and since the intake hole 114 provided on the bottom surface of the lower case 110 can be blocked during the installation process, a separate bracket 122 is used. It is preferable to install so as to be spaced apart from the intake hole 114 .

The bracket 122 includes a heating element support part 122a for supporting both sides of the PTC heating element 120 to be spaced apart from the intake hole 114, and a bottom surface of the lower case 110 provided to be horizontally bent at the lower end of the heating element support part. It may be composed of a coupling portion (122b) that is screwed or fitted to the.

As described above, the power line of the PTC heating element 120 is drawn out through the lead-out hole 112 of the lower case 110, and when not in use, it is wound around the winding protrusion 113 to arrange it.

The upper case 130 is incorporated in the upper part of the lower case 110, and as described above, when the lower case 110 is in the shape of an upper opening-type square box, the lower opening-type square box shape can be matched thereto. can be

Like the lower case 110, the upper case 130 may be made of a plastic material having low heat conduction, and a heat dissipation coating or a heat sink is installed on the inner surface of the PTC heating element 120 to prevent heat from being conducted to the outside. could be Since the reason has been described in the description of the lower case, it will be omitted.

An exhaust hole 131 through which air heated by the PTC heating element 120 is discharged may be formed on the upper surface of the upper case 130 . It is preferable that the vent hole 131 has a gap width of 5 mm or less to prevent the fingers of children, who are test subjects, from being inserted.

The upper case 130 is provided with another fastening hole 132 matching the fastening hole 111 of the lower case 110 at the edge thereof, and the two fastening holes 111 and 132 can be fastened by screws. .

The upper case 130 is provided with an inclined surface 133 on the upper edge portion, and a control module 134 for controlling the PTC heating element 120 may be provided on any one of the inclined surfaces. The control module 134 may provide an input unit for inputting a command on the inclined surface 133 in a touchpad manner to turn on/off the PTC heating element 120 according to a user's touch operation, or to set the temperature of the PTC heating element. have.

The inclined surface 133 also serves to guide the air heated by the PTC heating element 120 to the exhaust hole 131 . Therefore, the heated air is not dispersed and exhausted to the exhaust hole 131 , so that the air into the plastic bag 140 can be fed quickly and efficiently.

On the other hand, considering that the control module 134 may be overheated by the heating temperature when it exists in the same space as the PTC heating element 120 and an operation error may occur, the PTC heating element ( A heat shield plate 135 for space-separating the installation space of the 120 and the installation space of the control module 134 may be provided.

On the other hand, the PTC heating element 120 basically has a function of maintaining a constant temperature, but in case the temperature maintenance function is not properly maintained due to a failure, the heating temperature of the PTC heating element 120 is sensed in real time. and a temperature sensor (not shown) for transmitting the sensed temperature data to the control module 134 .

And, if the temperature value transmitted from the temperature sensor 150 is higher than the set temperature, the control module 134 regards the PTC heating element 120 as a failure and controls the power to the PTC heating element 120 to be cut off. Accordingly, even if the PTC heating element 120 fails, it is possible to prevent overheating beyond the set temperature. This is a kind of safety device.

The plastic bag 140 is disposed on the upper side of the upper case 130 and rises upward by the convection phenomenon of the hot air heated by the PTC heating element 120, thereby visually confirming the convection phenomenon. will be.

Since the plastic bag 140 has to be blown up like a balloon, it is not fixed to the upper case or the lower case, so that the opening of the plastic bag is located on the exhaust port 131 of the upper case 130. When a certain amount of hot air is injected into the inside of the bag, let it rise so that it can rise.

Here, on the surface of the plastic bag 140, a sticker 141, which is a heat discoloration means that is discolored according to the temperature of the air flowing into the inside of the plastic bag through the exhaust hole 131, is attached or an oil-based Zion paint is to be applied. can The thermochromic means is useful for learning effect because it is possible to visually check the temperature change of the air as the purple color changes to pink when the air temperature is 40° C. or higher.

In addition, a wire 142 such as a wire may be installed on the edge of the opening of the plastic bag 140 . The wire 142 helps smooth air inflow by maintaining the shape of the opening, and by placing the center of gravity of the plastic bag in the lower part, serves to stably drop the plastic bag when the hot air cools. .

What has been described above is only one embodiment for implementing a safety learning tool for examining the movement of heat in the gas according to the present invention, and the present invention is not limited to the above embodiment, and as claimed in the claims below. Likewise, without departing from the gist of the present invention, it will be said that the technical spirit of the present invention exists to the extent that various modifications can be made by anyone with ordinary knowledge in the field to which the present invention belongs.

100: safety learning aid 110: lower case
120: PTC heating element 130: upper case
140: plastic bag

Claims (4)

As a safety learning tool for experimenting with heat transfer in gas,
an upper opening-type lower case having an intake hole for inhaling external air;
a PTC heating element that is built into the lower case so as not to block the intake hole and generates heat by connecting a power source;
a lower opening-type upper case bound to the upper part of the lower case and having an exhaust hole for exhausting the heated air heat-exchanged at a high temperature by the PTC heating element; and
The opening is disposed on the exhaust hole so that the heated air discharged from the exhaust hole of the upper case flows into the inside, and a thermochromic sticker that changes color depending on the temperature of the introduced heating air is attached to the surface or is painted with oil-based Zion paint. A safety learning tool for testing the transfer of heat in a gas containing a plastic bag.
The method according to claim 1,
A control module for turning on/off the PTC heating element or setting a temperature is provided on one side of the upper case,
An experiment on the movement of heat in a gas, characterized in that by separating the installation space of the control module from other spaces, a heat shield plate is provided inside the upper case to block the heat generated by the PTC heating element from being transferred to the control module A safety learning tool to do.
3. The method according to claim 2,
and a temperature sensor for detecting the temperature of the PTC heating element in real time and transmitting the sensed temperature data to the control module,
The control module is a safety learning tool for testing the movement of heat in the gas, characterized in that the control so that the power to the PTC heating element is cut off when the temperature value transmitted from the temperature sensor is greater than or equal to the set temperature.
The method according to claim 1,
The PTC heating element is a safety learning tool for testing the movement of heat in the gas, characterized in that installed so as to be spaced apart from the intake hole by the brackets on both sides.

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