TO PRODUCE HEAT IN COATED GLASS

DESCRIPTION

This invention made possible that oxidized metals, which are conductors on one surface, can produce heat using much lower energy compared to similar products by way of the frequency, period and voltage of electricity applied to glass coating and the glass' resistance, in glasses with clear coating with a minimum 60% light transmittance ability that is achieved by way of PVD (PhysicalVaporDeposition), CVD (ChemicalVapourDeposition), sol-gel, chemical methods, electrochemical methods, thermal spray, hot-dip or any other methods.

Heat production on known coated glass is achieved by applying direct current (DC) to the coating on both sides. In applications with this method, glass dimensions are of limited size and are made only for small glassware and for low heat generation. The reason for this is that the minus (cathode) and plus (anode) poles of the direct current used are overheated at the connection points, which leads to glass malfunction. This method can be applied at 20 0 C temperature and on a 0,15 cm 2 area at most. Another known method is to heat the glass by connecting a 220 Volt alternating current (AC) which is a direct mains voltage to the covered glass. This method achieves a maximum temperature of 800 ⁰ C even though large size glass is heated. The reason for this is that there is no coating resistance that can withstand 220 volts alternating current, which is directly and continuously applied to the coating on the glass surface. For higher temperatures, the resistance needs to be lowered, which prevents the continuous 220 volt power supply to the coating from damaging the coating and causing it to burn out at high temperatures.

Another known method is to heat the coated glass using low alternating current. To obtain heat in low resistance glass, the glass is heated using a transformer that reduces the alternating current of 220 volts to a lower alternative current. In these applications, the glass temperature increases up to 20 ⁰ C. For this reason, this type of heating system is only used to defrost the glass doors of refrigerated cabinets. Another known method is the study case with the application no EP12707498.7 EPC. The subject of this patent is the heating method in transparent glass. The patent centers around a coating, which is applied onto at least one surface of a glassware and produces heat via parallel-connected electricity, and the related production method. The electrical parallel connection brings some constrictions such as limitations on resistance values of heat- producing transparent strip, size of the glass and magnitude of produced heat.

The implementation of silver paste on electricity bus tie, mentioned in this application (EP12711119.3), is a method applied on glass since 1960s. Since said silver paste busbar system is used in electric heating systems in vehicle rear windows, this is not a distinctive feature of this application.

In our application, there are no non-heated places since the coating, which produces heat via electricity on one surface of the glass, is coated to the whole surface rather than being in strips. In addition, this coating can be applied on laminated glass, single-piece glassware and in all areas glass is used, regardless of glass size and shape.

Another known method is the work with the application no EP11738179.8 EPC. In this patent, the subject is also a transparent coating, in strips, on at least one surface of the glass, and the electric connection to it. The application centers around serially connected heating areas in stripe form and the non-heated areas between these stripes. In addition, it was also reported in the application that the electric potential is between 100V and 400V and that this potential was applied by laminating two glass pieces. The study also reports that the coating must have a certain level of resistance, which necessitates a thickness level limit for heating strips. Limiting resistance value also limits the size of the glass the coating is to be applied on. Likewise, there is 100-400 Volts of high electricity consumption. Although it is mentioned that the electricity source used in this study is alternating voltage, there is no information on the frequency and period of electricity used. The study also reports that the implementation is for thawing on vehicles and architectural products. With the application methods mentioned in our application, a high heat production was made with very low electrical energy without any restriction on the type, size, thickness and resistance value of the glass. The frequency of electricity used, the period and the way of switching have made the energy consumption very low, independent of the type and thickness of the coating. Both laminated glassware and single-layered glassware have produced heat energy from glass thanks to the electrically conducting coating on the whole surface.

Another known method is the work with the application no EP12711119.3 EPC. This patent centers around temperature measurement method on heated glass, of which the EPC application number is given above, and around the method of controlling the source of electricity according to temperature.

Explanations are given as to how to connect the uncoated areas between heat-producing strips or how to connect the heat sensor using dye for the purpose of temperature measurement, together with explanations on how to convey electricity to the glass via the electronic circuit based on the value yielded by this sensor.

In our application, temperature measurement is considered as a cost increasing factor, therefore insulated dye and uncoated area formation procedures are skipped. A self- insulated thermocouple (temperature measurement device), which is a standard and commercially available device, was used.

Our invention enables heating of tempered glass up to 350°C and non-tempered glass up to 150°C, regardless of the size of a glassware, of which one surface is coated with electrically conductive coating. The reason for lower temperature yield on non-tempered glass the increasing risk of glass break due to expansion on glass surface due to heat. The glass must be tempered for higher temperatures. In addition, similar heat producers can yield the same level of temperature with a lower electric energy. The main pillar of the invention is the law of inertia. According to this law, every substance has a reaction magnitude and time against chemical and physical forces and every substance intends to return to its initial state by getting free of a force that is applied on it. And in order to return to its initial state, the substance tries to do this by transferring said applied force as temperature, light, radio waves, radiation, etc. to another field. The magnitude, speed and duration of an applied force determines how the substance will return to its initial state. A force that exceeds the substance's magnitude and time of reaction causes the substance to degenerate.

This invention enables it so that when you apply electricity to a coated surface of glass, which is coated with an electrically conductive coating with any method, said coating will produce heat using low energy and without degeneration.

One of the best examples for this invention is the springs made of steel. The metal, which constitutes the spring, can react to a certain magnitude of force applied on it for a certain amount of time, under normal circumstances. If the force is applied for a long time, the spring then gets deformed. However, when a force, with a magnitude greater than what the spring can carry, is applied for a very short period of time, the material works without degenerating. Springs are produced for this kind of works.

In terms of our invention, the coating on the glass is similar to the metal that constitutes the spring, and the force applied is similar to the electric energy. The coating intends to discharge the electric energy applied on it and return to its initial state. If no time is given to the coating for it to discharge the heat, which it produces as a reaction, then the coating gets deformed and malfunctions. With this invention, the reaction time and inertia time are provided via intermittent or truncated frequency form of the applied electric energy, therefore enabling achieving of high temperatures without damaging the coating.

Another example is to drive a nail into a surface such as wood or wall. The action of driving is achieved by applying a transient force onto the nail, which force is sufficient to drive it into the surface. However, when the same magnitude of force is applied onto the nail for a long time, the nail bends and does not drive through the surface. The reason for this is that the speed of the applied force is lower than the nail's reaction time. Unable to transfer this force onto the surface it's being driven through, the nail accumulates the force on itself and thus, bends. In the invention's method, the glass coating is similar to the nail and the electric energy is similar to the driving force applied. Tempered or non-tempered, an uninterrupted edge-long conductive line is formed by applying silver-containing paste or electrically conductive adhesive paste to the mirroring edges of glasses that are electrically conductive on one surface. This method of forming conductor lines has been used in automotive glass since the 1960s.

In tempered glass, a silver paste, which is resistant to tempering heat and electrically conductive, is applied on the glass and tempering is applied through a minimum of 600°C heat treatment and subsequent cooling. The purpose of this process is to permanently hold both the coating on the glass surface and the silver paste on the glass surface. The electrically conductive flat metal is then soldered onto one or more silver pastes, such as conductive silver-plated or aluminum or copper or zinc. Thus, the applied electricity is transmitted homogeneously and continuously to the conductive coating on the glass surface.In non-tempered glass, conductive flat metal is electrically bonded to the conductive coated surface of the glass with electrically conductive adhesive to provide electrical conductivity to the coating.

The resistance value which must be known for the application methods of the invention also relates to the silver paste or conductive adhesive to which the electrical connection is made. The effect of the silver paste or conductive adhesive applied to the glass coated surface on the coating resistance of the glass surface;

Can be calculated using the formula; R= q x L / A (Pouillet Law) Where R is the total resistance of the coating over the busbar; q is the total internal resistance of the coating and conductive silver paste or conductive adhesive; L is the length of the conductive silver paste or conductive adhesive on the glass surface; A is the area of the conductive silver paste or conductive adhesive. After resistance detection, one of the following two applications is selected by determining the current drawn by the coating according to Ohm's law. Because it draws very high currents at low resistances and because of the safety limitation of current limiting for domestic use, the method that draws the least current is selected. The system for achieving the object of the invention is described below with reference to the corresponding figures. These figures;

Figure 1- Electrical graphics for intermittent frequency method

Figure 1.1- A graphical view of network voltage frequency (50/60 Hz)

Figure 1.2-A graphical view of the first section switching frequency

Figure 1.3-A graphical view of intermittent outing of mains voltage frequency

Figure 2-Electrical graphics for truncated frequency method

Figure 2.1-A graphical view of mains voltage frequency (50/60 Hz)

Figure 2.2-Second stage switching frequency

Figure 2.3-A graphical view of mains voltage frequency in truncated outing

Figure 3- A graphical view of transformer voltage

The main idea of our invention is that heat is produced by applying electrical energy of variable frequency and amplitude to all the opposite sides of the glass with at least 60% light transmittance and electrical conduction connections as mentioned above. The mains voltage is used directly and the intermittent or truncated frequency methods of the mains frequency are applied. Furthermore, no electrical frequency source or generator is used. The inventive intermittent frequency method should not be confused with the inverter systems which operate according to the known frequency change discrimination. In inverter systems; The mains voltage is first converted to direct current (DC), and the sine waveform is formed by switching with the drive circuits. However, the frequency of this produced waveform is variable. The purpose of the inverter system is to control the operation of electrical devices by changing the generated frequency of the wave. The frequency applied to the device is variable as well as continuous. That is, the frequency applies electricity to the device throughout the entire wave without interruption at any instant.This is the use of certain fields of the 50/60 Hz waveform, which is directly the network frequency, without any artificial sine waveform with a frequency generator. The frequency used in connection is fixed mains frequency. As stated in the examples above, the coating on the glass surface must not be applied for a certain period of time to discharge over the heat generated by the applied electrical energy. However, during this non-electrical time, the glass should not fall below the desired heat value. The electricity applied as in the case of the nail should not overheat the coating on the glass surface and impair the coating's properties. A surface electrically conductive coated glass is applied to the intermittent and truncated frequency electric energy to produce permanent constant heat without degradation of the coating. This electric energy is made with an electronic circuit system and electricity is applied on the glass.

The subject of the invention is: In both methods mentioned below, the surcharge area (A) where electricity is applied to the coating on the glass surface and the time when it is not applied is called the passive area (P).

The circuit system of the intermittent frequency of the invention consists of two parts. The first part is a frequency switching circuit which determines the electrical energy output required to reach the desired temperature of the coating on the glass surface, which is the temperature step setting and communicates electrically with the temperature sensor on the glass. The second part is the switch which switches the mains voltage of the glass product to 50/60 Hz in cut-off sections (active areas (A)) to the flat metal in the glass- covered surface, by switching according to the frequency from the first part. The frequency switching circuit in the first section determines the switching frequency by taking the electrical difference between the electrical value coming from the thermocouple located on the glass and the set temperature value as a reference. With this method, the frequency of 50/60 Hz coming from the network to the glass surface is not continuously applied but is transmitted to the active areas (A) by dividing into active areas (A) and passive areas (P). It is ensured that the coating remains at a high temperature (tempered glass, approximately 3500C) without degrading and falling below the desired heat value.

This method differs from the lower or higher frequency electric energy in that it transmits the mains voltage to the covering within the determined time. In other words, this difference is that the potential in the sine waveform in the network transmits the voltage between the start and the end of switching (active area (A)) to the coating. At the time of switching, the transmission of the mains voltage starts and the cutoff at the end of the switching is eliminated. However, if a sine wave generator is used at the same frequency, all values between the zero voltage value and the peak value are applied to the plasma. This causes the coating to lose its properties because it will not be able to identify the time for heat sinking. The continuous and slow electrical energy, such as the nailing force in the nail driving example, deforms the coating in a short time.

Another method of the invention is the truncated frequency method. This method should not be confused with known dimmer electric systems we will explain below. The difference of this method from the dimmer circuits is to determine the most suitable clipping point of the network frequency by monitoring the temperature of the monitoring system and the glass. As is known, there is no such method in dimmer circuits. RMS outputs exceeding the rated 16 amps load (30 amps) are given for domestic use, thus damaging other equipment connected to mains electricity and also creating a hazard by drawing current on the peak current limiter.

Truncated frequency method consists of three parts. The first part is the circuit that follows the network frequency and sends the second division switching threshold signal, and the second part is the part that switches by referring to the temperature value difference set by the temperature sensor electrical value on the glass when the signal comes from the first part. The third part is the part that transfers to the flat metal (conductors) on the coating on the glass surface by trimming the frequency of the mains voltage with the switching from the second part.

The mains voltage, which is known as 50/60 Hz, draws a sinusoidal graph from zero to peak. 900 phase difference occurs between the peak value and the zero value, falls to 0 volt again, and then goes to the negative alternation. The first part of the truncated frequency system, the mains frequency monitoring section (Figure 1.1), indicates the appropriate phase angle required for switching. Thus, the parasitic currents that damage the network to other devices do not go away, and the electrical energy used by the glazed window is also adjusted to within the specified limits and the RMS values. The second part circuit (Figure 1.2), which receives the switching signal from the first part, opens the power switch in the third part by generating the output signal according to the temperature value difference set by the measured temperature value. Here, covered mains voltage is transmitted using the mains voltage (active area (A)) to generate heat. No electrical conduction to the glass product during the period that the power switch is closed (passive area (P)). The truncated frequency method allows the use of a voltage value below 900 peak of mains voltage and other equivalent phase angle voltage values. With this method, there is a distinctive difference between the transformer devices and the reduced mains voltage when a low mains voltage is used. Transformers can provide continuous electrical output at 50/60 Hz frequency, which is lower than the mains voltage. That is, there is continuous voltage output between 0 and peak value. Whereas in order for the glass surface coating to work without degradation, it needs to discharge the heat on itself, which requires a certain amount of time during which no electric energy is applied. Since the transformer output is continuous, the invention cannot be used in place of the truncated frequency method since the output voltage does not allow the heat transfer of the coating even if the output voltage is the same as the truncated frequency voltage.

As can be seen in the graphs of Figure 1.3 (truncated frequency voltage) and Figure 3 (transformer output voltage), the transformer does not have time to transfer the current heat of the coating because the transformer has applied constant voltage even though the truncated frequency voltage and transformer output voltage are the same. This causes the coating to be damaged. However, with the inventive method, both efficient and efficient heat generation is achieved without damaging the coating, without using heavy and costly reducers such as transformers. One application made possible by the invention is to obtain heat by applying utility voltage to the coated glass by the intermittent frequency method. For example, voltage is applied for 1/3 of a second (active area (A)), no current is applied for the remaining 2/3 (passive area (P)). In other words, when the intermittent frequency is used, switching is effected at predetermined times as the electric frequency transmitted to the casing follows the sine waveform advancing from 0 ⁰ to 90 ⁰ and from 90 ⁰ to 180 °. This switching is transmitted to the electric enclosure in the drive train. According to the sine wave form, the electric frequency is the lowest at 0 ⁰ and the highest at 90 °. In the intermittent frequency method, when the electric frequency advances from 0 ⁰ to 90 °, the voltage value at each switching time is higher than the previous value. For example, when the voltage in the first active area (A) is between 30-40 V, the voltage in the next active area (A) is 50-60 V. When the electric frequency follows the sine waveform and advances from 90 ⁰ to 180 °, the voltage value in the active area (A) generated by the switching is lower than before. In this way, the voltage values in the active areas (A) formed by switching in the intermittent frequency method are firstly increased and transmitted to the cover in a truncated manner. The voltage values of the active areas (A) which are formed later are reduced and transmitted to the coating in an intermittent manner. This process goes on in a cyclic manner. The voltage values of the active areas (A) formed in the intermittent frequency method are given to the coating at certain intervals, not as a constant. The active area (A) is the value of the electric voltage between the switching start and the switching end where the switch is made.

The distinguishing feature of this application (intermittent frequency method) is that high resistance glasses can achieve a temperature of 3500C in a short time with low electric energy. It also produces the same heat with very low electrical energy and is more efficient than the comparably large-scale similar products used as the heater panel.

Another application of the invention is to obtain heat by applying alternating voltage to the coated glasses. Depending on the amount of heat to be produced from the coated glass, a certain fraction of the frequency of the network is given as the active area (A), while the remaining parts remain as the passive area (P).

The distinguishing feature of this application (the truncated frequency method) is that low resistance glass of low resistivity allows the temperature to reach 350 C in a short time.

In other words, as the voltage values of the electric frequency given to the glass product start to move from 0 ⁰ to the sine wave form and rise, the voltage is applied to the active area (A) formed by switching. The passive area (P) is then started and advances to 90 ⁰ and again to 180 °. When the voltage of the previous active area (A) falls to the voltage value, the switch is again switched and the electricity is transmitted to the coating. In this way, the active area (A) formed by switching when the electric frequency reaches only the specified voltage value is transmitted to the coating. The part that is outside of the switch is the passive area (P) and is not transmitted to the coating. Thus, the voltage value in the active areas (A) can be applied to the coating and the glass heats without degrading the coating.

Among the above mentioned methods, the choice is determined by the resistance value measured over the conductor edge lines, the amount of heat desired and the time to reach this level. The voltage to be drawn by the glass according to the Ohm law is determined by the time and desired heat value. This current should not exceed 16 Amperes in household use. This current is then calculated in the resistance and time format according to Joule's law and one of the above mentioned cut or trimmed frequency methods is selected for the glass to be heated.

I = V / R (Ohm Law)

I = Current ( Ampere)

V = Voltage (volt)

R = Glass resistance (ohm)

W = I ² x R x T (Joule Law)

W= Electric energy converted to heat (Joule)

I = Current (Ampere)

T = Time (duration of electric energy application, in seconds)

The amount of electricity used is also calculated according to Watt's blood, proving the advantages of the inventive methods.

P = I x V (Watt Law)

P = Electric power consumed (watt)

I = Consumed current (ampere)

V = Voltage applied (volt) As an example application, to heat the glass at 23 cm x 37 cm to 240 ⁰ C, conductive lines are first applied to the edges of the glass as described above, and tempering is done.

In the case of the invention, conductive silver paste is applied to the short sides of some of the same sized glasses entering the tempering process, to the long sides of some of them, as an example of cut or trimmed frequency selection. In the tempering process, the conductive silver paste and the electrically conductive coating have become permanently embedded in the glass.

Resistance measurements were then made on the glass through the conductive paste. The resistance of the glass on the short side of the conductor is 20 ohms.

The resistance of the glass on the long side of the conductor is 8 ohms.

According to these measurements;

The glass with the 20 ohm resistance will draw I = V / R = 220 volt / 20 ohm = 11 Amperes of current.

The glass with the 8 ohm resistance will draw I = V / R = 220 volt / 8 ohm = 27,5 Amperes of current.

According to these current values, both glasses will not reach the same temperature at the same moment and according to the Joule Law, the glass with the 8 ohm resistance value will reach a higher temperature. In order for the 8-ohm resistance glass to reach the same temperature as the 20-ohm resistance glass, the applied voltage should be lowered to 11 amperes of current value. Thus, the voltage to be applied to the 8-ohm resistance glass is; According to the I = V / R Ohm Law, V = I x R = 11 ampere x 8 ohm = 88 volts.

Truncated frequency is selected in order to apply a maximum of 88 volts for this voltage value. The mains voltage in the sine wave form is applied to the covering up to 88 volts voltage size while starting from 00 to 900. The voltage over 88 volts is not applied to the coating and it stays in the passive area (P). While going down again from 90° to 180°, at the moment of reaching 88 volts electricity transmission to the coating starts, therefore forming an active area (A).

Since the value of the voltage to be drawn by the glass at 20 ohm resistance is under 16 amperes, which is the household current value, intermittent frequency is applied to produce the desired heat. Here the switching frequency is 20Hz. That is, 40% of the mains voltage, which is 50Hz, is used. When the 50Hz mains voltage is directly applied, the glass reaches desired heat level in 1-2 minutes. However, if desired heat level is to be achieved in 3 minutes, this means a 40% extension in time. This corresponds to 20Hz, which is 40% of 50Hz frequency. The power to be consumed by the glass when mains frequency is applied without interruption;

Using the P = I x V formula

P = 11 amperes x 220 volts = 2420 watt.

However, since glass uses not all, but only 40% of the 50Hz voltage to produce heat, the electricity consumed by the glass is;

P ( _g iass)= 2420 watts x 40% = 968 watt.

As seen in Figure 1.3, active areas (A) total 40 units and passive areas (P) total 60 units. This shows that the inventive cut-off frequency method is advantageous and distinguishable compared to similar heat generators since it provides lower energy consumption.

All operations from 0° and 90° for the above-mentioned sine waveform in the context of the present invention also apply between 180° and 360°. For easier understanding, the sine wave form has been mentioned between 0° and 180° in the positive alternation region.

As mentioned above, the energy consumption of the coating is lower because neither of the grid voltage (truncated frequency and intermittent frequency) is applied to the coating on the glass surface and the network frequency is divided into active area (A) times and passive area (P) times. Known equivalent heat generators generate heat using all frequency ranges of the mains voltage. With the method according to the invention, since no electricity is used in the passive areas (P) of the grid frequency in the coating on the glass surface, heat is generated with less energy.

With this invention, heat production is made independently of the size of the glass, allowing the application and heat generation with small and cheaper electronic cards instead of heavy and expensive materials such as transformers. With this invention, many products such as glass grill, toaster, toaster, baking utensils such as oven tray, heated table, heater heating panels, defogging small glass and vehicle glass can be produced as heating glass.