JPH0431076A - Cooling device of copying machine - Google Patents

Abstract

PURPOSE:To provide only are fan or only at one place and thereby cool a recording device and a reading device efficiently by arranging the fan which generates an air stream in such a manner that the air is allowed to run from the recording device to the reading device and then is exhausted, between the recording device and the reading device. CONSTITUTION:The heat generating amount of an ink discharge part 9 is smaller than that of a lamp, and the maximum temperature conditions of the ink discharge part 9 are lower than those of the reading device 200. In view of this fact, a fan 13 is arranged between a recording device 100 and the reading device 200. Air is blown from a suction orifice 14 to a discharge orifice 15 through the interior of the recording device 100 and the interior of the reading device 200, in a duplicator. Next, the air from outside absorbs heat from the ink discharge part 9, to begin with, and then the same air absorbs heat from inside the reading device. Thus it is possible to absorb heat from inside the reading device efficiently and cool the entire duplicator efficiently only by a single fan 13 provided at on place.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a cooling device for a copying machine equipped with a recording device and a reading station.

(Prior Art) A copying machine is equipped with a reading device that reads a document and forms an image signal, and a recording device that records an image on a sorted recording material such as paper or a thin plastic plate based on the image signal. ing.

The recording apparatus can be divided into inkjet type, wire cartridge type, thermal type, laser beam type, etc., depending on the recording method of the recording head. Among these, the inkjet type (inkjet recording apparatus) uses ink from the recording head to the recording material. It is configured to eject and perform recording.

Inkjet recording apparatuses have advantages such as low noise because they are non-impact type, and the ability to easily record color images using multicolored inks.

A film boiling type inkjet recording apparatus has been proposed in which recording is performed by ejecting ink using thermal energy.

In this film boiling type inkjet recording device,
An electrothermal transducer (heating element) is provided corresponding to each ejection port of the recording gutter, and while supplying ink to the recording gutter, a driving pulse is applied to the electrothermal transducer in accordance with an image signal,
The ink is configured to be ejected from the ejection port using the thermal energy generated at that time.

In such a recording device that uses thermal energy, heat tends to accumulate in the recording section (the ink ejection section in the case of an inkjet type), and the temperature of the recording section rises each time recording is repeated, causing the temperature of the recording section to become high. If it becomes too much, the ink ejection conditions will deteriorate in the inkjet method, and the image quality will deteriorate due to ejection failure and the like.

Therefore, a cooling device is required to cool the recording section (ink ejection section).

Furthermore, copying machines usually use an optical reading device that uses a halogen lamp or the like as a light source for reading originals.

Since halogen lamps emit a large amount of light and also generate high heat, the temperature of the document glass on which the document is placed increases, which may cause a user to touch it and suffer burns.

Additionally, when the temperature of parts surrounding the lamp, such as lenses and optical sensors, rises, their performance will decrease and there is a possibility that they may not operate properly.

Therefore, in the reading device of a copying machine, it is necessary to cool the vicinity of the lamp, the original glass, and the like.

As described above, in a copying machine using an inkjet recording device, it is necessary to cool both the recording device having the ink ejection section and the reading device having parts near the lamp and the document glass.

FIGS. 5 and 6 are front sectional views showing examples of the configuration of a conventional cooling device for a copying machine, respectively.

In the conventional example shown in FIG.
0 is provided, and the reading device 200 has a reading means 210.
Separate fans are provided in each of the recording device 100 and the reading device 200, such as a fan 220 for cooling the vicinity of the lamp and the original glass l on which the original is placed.

On the other hand, in the conventional example of the sixth section, one fan 150
The air sent out from the recording device 100 and the reading device 200 were separately blown.

[Technical problem to be solved by the invention] However,
The conventional example shown in Fig. 5 requires two fans 110 and 220, which increases the cost, and in the case of a small copying machine, installing two fans is necessary to secure space. There was a technical problem that caused unreasonableness.

On the other hand, in the conventional example shown in FIG. 6, there is only one fan, but since the air sent out by the fan 150 needs to be divided into two, the amount of air flowing to each of the recording device 100 and the reading device 200 is reduced. There was a technical problem in that the cooling effect decreased.

The present invention has been made in view of such conventional technical problems, and provides a cooling method for a copying machine that can efficiently cool both the recording device and the reading device by simply providing one fan or one fan at one location. The purpose is to provide equipment.

[Means for Solving the Problems] The present invention provides that the maximum temperature condition of the reading device is higher than the maximum temperature condition of the ink ejection portion, and that the amount of heat generated by the ink ejection portion is higher than the amount of heat generated by the lamp of the reading device. This was done with a focus on small size, and a small fan was placed between the recording device and the reading device, and the outside air was first circulated into the recording device, then into the reading device, and then the outside air was By configuring the discharge to
This aims to achieve the above objectives.

By the way, the current maximum temperature condition for the ink side recording head is around 50°C, the maximum temperature condition for the document glass is around 85°C, and the maximum temperature condition for the short focus lens array (SLA). is around 50°C.

That is, the present invention provides a cooling device for a copying machine that includes a recording device and a reading device. By arranging a fan that generates the amount of energy between the recording device and the reading device, it is possible to efficiently cool both the recording device and the reading device by simply providing one fan or one fan. This provides a cooling system for the machine.

In such a configuration, if an intake port and an exhaust port are provided on one side of the copying machine, and a fan is provided inside the copying machine on the other side, the fan and the intake/exhaust port are separated, so the intake and exhaust port is placed next to the fan. Compared to conventional structures in which fans are arranged, fan noise is less likely to leak outside, reducing noise.

In addition, in such a configuration, if the air intake port and the fan are arranged so as to blow air in the recording direction of the recording device, ink droplets ejected from the recording head are less likely to be swept away by the wind. , it is possible to form an image at a stable position with respect to the recording material.

(Example) Hereinafter, the present invention will be described in detail with reference to FIGS. 1V to 3.

The first part is a front sectional view showing an embodiment of a copying machine equipped with a cooling device according to the present invention, and FIG. 2 is a side sectional view of FIG. 1.

First, the operation of the copying machine will be explained using FIGS. 1 and 2.

In FIGS. 1 and 2, the original placed on the original glass 1 is moved to the main scanning carriage 2 of the reading device 200.
While moving the document in the six directions of arrows (FIG. 2), the lamp 3 illuminates the document, and the sensor 4 detects the reflected light, thereby reading a fixed width at a time.

A reading means 210 consisting of the lamp 3, sensor 4, etc. is mounted on the main scanning carriage 2.

On the other hand, in the recording apparatus (inkjet recording apparatus) 100, a notebook-shaped recording material 5 such as paper or a plastic thin plate is conveyed to the recording section 8 by a paper feed roller 6 and a recording material transport roller rough.

Therefore, the carrier 7. with the recording head 9 mounted thereon. , ; While moving the recording device 11 in the direction of arrow C (Fig. 1), read the read signal (electrical signal) from the sensor 4.
By ejecting ink based on this, an image of a constant width is recorded on the recording material 5.

In the illustrated example, the recording nozzle (ink ejection unit) 9 has four head portions 9A, 9B, and 9C89D, and in the case of color recording, these head portions are, for example, yellow,
It can be made compatible with magenta, noan, and black ink colors.

Further, an ink tank l0A-1 in which ink of a corresponding color is stored is provided above each head portion 9A to 9D.
0D is provided integrally, and has a cartridge configuration.

Each of the head cartridges of each color, consisting of the nozzle part and the ink tank head part, is removably attached to the ball scanning carrier of the recording apparatus.

Therefore, as mentioned above, when the carino:;'II moves in the direction of arrow C, a color image of a constant width is formed by ejecting ink of each color onto the recording material 5 based on the electrical signal from the sensor 4. be done.

For recording, G9 is an inkjet recording head that ejects ink using thermal energy, and is equipped with an electrothermal transducer for generating thermal energy.

Further, in the inkjet recording, the do 9 performs recording by ejecting ink from the ejection port by the growth of bubbles due to film boiling caused by thermal energy applied by the electrothermal converter.

When a certain width of recording is completed by the main scanning of the carriage 11 mentioned above, the sub-scanning carriage 12 of the reading device is moved by a certain width in the direction of arrow B (FIG. 1), and the recording material 5 is moved by the conveying roller rough. The image of the next fixed width of the document is recorded on the recording material 5 by conveying the original by a certain width and performing the same operation as described above.

By repeating the above reading and recording operations, the image of the document is copied onto the recording material 5.

Next, the cooling device for the copying machine described above will be explained.

An intake port 14 leading into the recording device 100 and an exhaust port 15 from the reading device 200 are provided on the left side of the copying machine, and the position between the recording device and the reading device inside the right side of the copying machine is A cooling fan 13 is provided.

Fins 16 are provided at the outlet of the fan 13 to rectify the discharged air.

When the fan 13 operates, outside air is taken in through the intake port 14, and wind flows inside the recording device 100 as indicated by arrow a.

The heat of the recording head (ink ejecting section) 9 is absorbed by this wind a.

Here, the positional relationship between the intake port 14 and the fan 13 is such that the feeding air (wind in the same direction) is relative to the recording direction of the recording apparatus, that is, the moving direction C of the carriage 11 during recording.
It has been selected to be.

The wind that has absorbed the heat of the recording head 9 is moved by the fan 13.
Furthermore, the air flows inside the reading device 200 as a wind as indicated by the arrow.

The heat of the lamp 3 and its vicinity, as well as the heat of the document glass 1, is absorbed by the wind in the direction of the arrow, and the hot air (air) whose temperature has risen due to the absorbed heat is transferred to the exhaust port 1.
5 and is discharged to the outside.

Further, in this embodiment, the wind from the fan 13 into the reading device 200 is also flowed in the direction of arrow d (FIG. 2), so that the wind in the direction of the arrow flows uniformly inside the reading device. has been done.

In the embodiments shown in FIGS. 1 and 2, the stop position of the main scanning carriage 11 of the recording apparatus 100 after recording and the standby position during continuous copying (when feeding the recording material 5) are at the recording unit 8.
Therefore, the stop position of the ink ejection unit (recording head) 9 on the carriage II after recording and the standby position during continuous copying are outside the range of It is set near the intake port 14 indicated by the arrow in FIG.

Further, the stop position of the main scanning carriage 2 of the reading device 200 after recording and the standby position during continuous copying (when feeding the recording material 5) are as shown by arrow E in FIGS. 1 and 2. Therefore, the stop position of the reading means 210 consisting of the lamp 3 and the sensor 4 on the carriage 2 after recording and the standby position during continuous copying are as shown in FIG. It is set near the fan 13 as shown by arrow E in FIG.

The recording head 9 and reading means (lamp 3, sensor 4, etc.) 210 are configured to rotate for a predetermined period of time or longer when the recording head 9 and reading means (lamp 3, sensor 4, etc.) 210 are stopped or on standby.

According to the embodiment described above, the amount of heat generated by the ink discharge section 9 is smaller than the amount of heat generated by the lamp 3, and the amount of heat generated by the ink discharge section 9 is smaller than that of the lamp 3.
Considering that the maximum temperature condition of is smaller than the maximum temperature condition of the reading device, the recording device 100 and the reading device 200
A fan 13 is placed between the intake port 14 and the copying machine.
→ Inside the recording stack 100 → Inside the reading device 200 - A flow of wind is generated in the direction of the exhaust port 15, and the wind from the outside first absorbs the heat of the ink ejection part 9, and then the same wind is used to read the data. Since the structure is configured to absorb the heat inside the reading device, the heat inside the reading device can also be effectively absorbed, and by using the fan 13 efficiently, copying can be performed with only one or one fan 13. A cooling device that can effectively cool the entire machine is obtained, and since the intake port 14 and the exhaust port 15 are separated from the fan 13, compared to the conventional structure in which the intake and exhaust ports are provided next to the fan, there is less fan leakage to the outside. 13, and the noise of the copying machine could be reduced.

Furthermore, the positional relationship between the air intake port 14 and the fan 13 is selected so as to provide a blowing air (wind in the same direction) with respect to the recording direction of the recording apparatus 100, that is, the moving direction C of the carriage 11 during recording. As a result, the ink droplets ejected from the ink ejection section 9 are less likely to be blown away by the wind, and the recording material 5
It was possible to record stable images at accurate positions.

Further, the stop position after recording of the recording head 9 having an ink ejection section and the standby position during continuous copying (when feeding the recording material 5) are set near the intake port 14, and the reading means having the lamp 3 is set. The stop position after recording is completed and the standby position during continuous copying (when feeding the recording material 5) are set near the outlet of the fan 13, and the fan 13 is rotated for a certain period of time or more during these stops and standbys. Therefore, the ink discharge section 9 and the vicinity of the lamp 3 of the main scanning carriage 2 of the reading device can be cooled with the wind with the smallest temperature rise, and the ink discharge section 9 and the vicinity of the lamp 3 can be efficiently cooled. was completed.

FIG. 3 is a front sectional view showing another embodiment of the cooling device for a copying machine according to the present invention.

In this embodiment, a square fan 17 is used in place of the cross-flow type fan 13 in the previous embodiment.

The other parts of this embodiment have substantially the same structure as those of the embodiments shown in FIGS. 1 and 2, and corresponding parts are designated by the same reference numerals, and detailed explanation thereof will be omitted.

The embodiment shown in FIG. 3 also provided the same effects as those of the previously described embodiment.

FIG. 4 is a front sectional view showing still another embodiment of the cooling device for a copying machine according to the present invention.

In the inkjet recording device used as the recording device 100, ejection failure may occur due to ink sticking or ink thickening occurring in the ink ejection portion 9, or bubble generation inside the ejection port.

As a means to recover from this ejection failure, the ink is ejected at a predetermined timing by sealing the ink ejection part with a cap and sucking ink from the ejection port using negative pressure generated within the cap by a pump. or discharge) is used.

The waste ink discharged in this way is passed through a tube etc.
The waste ink is stored in a waste ink storage unit consisting of a tank or container.

Reference numeral 120 in FIG. 4 indicates this waste ink storage section.

In this embodiment, in the copying machine (conventional example) shown in FIG.
The wind after cooling the lamp 3 and sensor 4) 210 and the original glass 1 are guided to the waste ink storage section 120, and this heated wind (air) is used to remove the waste. After heating the waste ink in the ink storage section 120, the cough air is discharged to the outside of the device.

In FIG. 4, the fan 15 is disposed on the right side inside the copying machine between the recording device 100 and the reading device 200, and an air intake port 160 is formed near the fan 150.

Also, the reader 2 is located on the left side inside the copier.
The wind Y in 00 is transferred to the waste ink storage section 12 in the recording device 100.
A ventilation path +70 is formed to lead to the air.

The hot air Y from the ventilation path 170 merges with the hot air
0, then heat the left side of the copying machine (waste ink storage section 1).
It is discharged to the outside of the device from an exhaust port 180 formed in the vicinity of 20).

According to the embodiment described above with reference to FIG. 4, the evaporation of the liquid component of waste ink (usually accounting for 70 to 90% of the ink volume) is promoted by hot air generated using the heat source inside the copying machine. In addition, since the evaporated gas is discharged to the outside by the flow of exhaust heat air, the amount of waste ink inside the waste ink storage section 120 can be significantly reduced, and therefore the volume of the waste ink storage section 120 can be significantly reduced. A copying machine that can be made smaller and has a more compact device configuration has been obtained.

In the illustrated example, since both the hot air X from the recording device 100 and the hot air Y from the reading device 200 are used, the evaporation of the liquid component of the waste ink can be promoted more effectively.

Furthermore, since the evaporated gas is discharged to the outside, it is possible to prevent the gas from condensing inside the copying machine, thereby preventing short-circuiting of electrical components and staining the back side of the document glass 1.

In the embodiment shown in FIG. 4, the hot air applied to the waste ink storage section 120 is discharged through the exhaust port 180.
It is also possible to configure such that hot air from 0 is applied to the waste ink storage section 120 and then directly discharged to the outside of the copying machine through a duct or the like to isolate it from the inside of the copying machine.

If the configuration is such that the hot air is directly discharged outside the copying machine, no water vapor will be generated inside the copying machine.
It is possible to eliminate recording defects caused by water droplets and the like.

In this case, it is preferable that the hot air outlet is provided in an area before and after the recording section 8 of the recording material 5 (FIG. 2) and on a side surface different from the discharged paper storage stonk area.

In the above embodiments, the present invention was explained by taking as an example a case where the present invention is applied to a copying machine using a serial scan type inkjet recording device in which the recording head 9 moves in the direction of arrow C. , it can be similarly applied to copying machines that use inkjet recording devices of other recording methods, such as line-type inkjet recording devices that use line-type recording heads that cover the recording area of the recording material in the paper width direction. , similar effects can be achieved.

Further, in the above embodiment, four head portions 9A to 9D
Although the case of using a full-color inkjet recording device using When using an inkjet recording device for gradation recording using multiple heads, etc.
It can be applied in the same way regardless of the number of heads, and the same effects can be achieved.

The present invention provides excellent effects particularly when the recording apparatus 100 uses an inkjet recording head of the bubble jet method proposed by Canon Co., Ltd. among inkjet recording methods.

As for typical configurations and principles thereof, it is preferable to use the basic principles disclosed in, for example, US Pat. No. 4,723,129 and US Pat. No. 4,740,796.

This method can be applied to both the so-called on-demand type and the continuous type, but especially in the case of the on-demand type, it is necessary to place the liquid (ink) on the sheet or liquid path where it is held. generating thermal energy in the electrothermal transducer by applying at least one drive signal corresponding to the recorded information and causing a rapid temperature rise above nucleate boiling to the electrothermal transducer; This is effective because film boiling is caused on the heat-active surface of the recording head, resulting in the formation of bubbles in the liquid (ink) in one-to-one correspondence with this drive signal.

This bubble grows and collects! A liquid (ink) is ejected through the ejection opening from one side to form at least one drop.

If this drive signal is in the form of a pulse, bubble growth and contraction will occur immediately and appropriately, so liquids with particularly excellent responsiveness (
Ink) can be ejected, which is more preferable. As this pulse-shaped drive signal, those described in US Pat. No. 4,463,359 and US Pat. No. 4,345,262 are passed.

Further, if the conditions described in US Pat. No. 4,313,124 concerning the temperature increase rate of the heat acting surface are adopted, even more excellent recording can be achieved.

The configuration of the recording head includes a combination configuration of an ejection port, a liquid path, and an electrothermal converter (straight liquid flow path or right-angled liquid flow path) as disclosed in each of the above-mentioned specifications. U.S. Pat. No. 4,558,333 and U.S. Pat. No. 4,459,60 disclose a configuration in which the portion is arranged in a bending region.
A configuration using the specification of No. 0 is also included in the present invention.

In addition, Japanese Patent Application Laid-open No. 123670 of 1982 discloses a configuration in which a common slit is used as a discharge part for a plurality of electrothermal converters, and a hole that absorbs pressure waves of thermal energy is disclosed. The present invention is also effective as a configuration based on Japanese Patent Application Laid-Open No. 138461 of 1981, which discloses a configuration in which a discharge portion corresponds to a discharge portion.

Furthermore, as a full-line type recording head having a length corresponding to the width of the maximum recording medium that can be recorded by the recording device, the length can be increased by combining multiple recording nodules as disclosed in the above-mentioned specification. Either a configuration that satisfies the above requirements or a configuration as a single recording gutter formed integrally may be used, but the present invention can more effectively exhibit the above-mentioned effects.

In addition, by being attached to the main body of the device, it is possible to make electrical connections with the main body of the device and supply ink from the main body of the device. The present invention is also effective when using a cartridge type recording head.

Further, it is preferable to add recovery means, preliminary auxiliary means, etc. for the recording head, which are provided as a configuration of the recording apparatus of the present invention, because the effects of the present invention can be further stabilized.

Specifically, these include capping means, cleaning means, pressure or suction means, preheating means for the recording head using an electrothermal transducer or another heating element, or a combination thereof. It is also effective to perform a preliminary ejection mode in which ejection is performed separately from printing in order to perform stable printing.

Furthermore, the recording mode of the recording device is not limited to a recording mode of only mainstream colors such as monochrome, but may also include a recording head that is configured integrally or a combination of multiple colors, or a recording mode that uses multiple colors of different colors or a mixed color. The present invention is also extremely effective for devices equipped with at least one full color image.

In the embodiments of the present invention described above, the ink is explained as a liquid, but it is an ink that solidifies at room temperature or lower, and is softened or liquid at room temperature, or in the above-mentioned ink jet, the ink itself is heated at 30'C or higher. Since the temperature is generally controlled within a range of 70° C. or less so that the viscosity of the ink is within the stable ejection range, it is sufficient that the ink is in a liquid state when the recording signal is applied.

In addition, it is possible to actively prevent temperature rise due to thermal energy by using it as energy to transform the ink from a solid state to a liquid state, or to prevent ink from evaporating when it is left to solidify. In any case, ink may be liquefied by applying thermal energy in response to a recording signal and ejected as liquid ink, or it may already begin to solidify when it reaches the recording material. It is also applicable to the present invention to use ink that is liquefied only by thermal energy.

In such a case, as in Japanese Patent Application Laid-open No. 54-56847, the ink is held as a liquid or solid in the recesses or through holes of the porous notebook and is placed facing the electrothermal transducer. It may be in any form.

In the present invention, the most effective method for the above-mentioned ink is one that implements the above-mentioned film boiling force formula.

[Effects of the Invention] As is clear from the above description, according to the present invention, in a cooling device for a copying machine equipped with a recording device and a reading device, outside air is taken in from the intake port, and the outside air is read from the recording device. The configuration is such that a fan that generates a flow of air is placed between the recording device and the reading device so that it passes through the device and exhausts the air afterwards. A cooling device for a copying machine is provided that can efficiently cool both the device and the reading device.

In addition, the intake and exhaust ports are provided on one side of the copying machine, and the fan is installed inside the copying machine on the opposite side, so the fan and the intake and exhaust ports are separated from each other. Compared to the structure, a cooling device for a copying machine was obtained in which the sound of the fan is less likely to leak outside, and the noise can be reduced.

Furthermore, the air inlet and fan are arranged so that they blow air in the recording direction of the recording device, making it difficult for the ink droplets ejected from the recording head to be blown away by the wind, making them stable against the recording material. A cooling device for a copying machine capable of forming an image in position is obtained.

[Brief explanation of the drawing]

FIG. 1 is a front sectional view showing one embodiment of the cooling device for a copying machine according to the present invention, FIG. 2 is a side sectional view of FIG. 1, and FIG. 3 is another embodiment of the cooling device for a copying machine according to the present invention. 4 is a front sectional view showing still another embodiment of the cooling device for a copying machine according to the present invention; FIG. 5 is a front sectional view showing one side of the cooling device for a conventional copying machine. , and FIG. 6 is a front sectional view showing another example of a conventional cooling device for a copying machine. Below, symbols representing main components in the drawings are listed. 1-1111 Original glass, 2-King scanning cartridge (reading device), 3----Lamp, 4--Sensor, 5
---1 recording material, 6--feeding roller, 7-conveying roller (recording device), 8--1 recording section, 9.9A to 9
D----Recording head (ink ejection part), 10.10
A~10D--ink tank, 11--main scanning carriage (recording device), 12--sub-scanning carriage (reading device), 13--fan, 14 air intake port, I5-exhaust port, I7- fan , 100--recording device, 120-
--Waste ink storage unit, 150---Fan, 16
()--1 intake port, ]70 ventilation passage, 180-exhaust port,
200--1-Reading device, 210-Reading means. 1 (p Hat damage mouth key ≦ mouth 10T

Claims (6)

[Claims] (1) In a cooling device for a copying machine equipped with a recording device and a reading device, outside air is taken in through the intake port, and the outside air is
After passing from the recording device to the reading device, exhaust the air.
A cooling device for a copying machine, characterized in that a fan that generates a flow of air is disposed between the recording device and the reading device. (2) The cooling device for a copying machine according to claim 1, wherein an intake port and an exhaust port are provided on one side of the copying machine, and a fan is provided inside the copying machine on the opposite side. (3) The cooling device for a copying machine according to claim 1, wherein the air intake port and the fan are arranged so as to blow air in the recording direction of the recording device. (4) The stop position of the recording head having an ink ejection unit after the end of recording and the standby position during continuous copying are set near the intake port, and the stop position of the reading means having a lamp after the end of recording and the standby position during continuous copying are set near the intake port. 2. The cooling device for electronic equipment according to claim 1, wherein the fan is positioned near an outlet of the fan, and the fan is rotated for a predetermined period of time or more when stopped or on standby. (5) The recording head of the recording device is an inkjet recording head that ejects ink using thermal energy and is equipped with an electrothermal converter for generating thermal energy. The cooling device for a copying machine according to claim 1. (6) The copying machine according to claim 5, wherein the recording head ejects the ink from the ejection port by the growth of bubbles due to film boiling caused by the thermal energy applied by the electrothermal converter. Cooling system.