JP2002305316A - Method and device for manufacturing solar battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technology that solves the problem of performance drop of a photovoltaic element which occurs when the element receives a tensile strain in a method of manufacturing a solar battery in which the photovoltaic element and sheet-like resin are integrated by means of the pinching pressure of a pair of rotating rollers by passing the element and resin between the rollers. SOLUTION: A mechanism which prevents a strain exceeding an FF lowering critical value from being generated in the photovoltaic element 3 by a difference in transporting force in a pinching section where the element 3 is pinched by the paired adjacent rollers 1 and 2. Alternatively, the strained amount of the element 3 is directly or indirectly detected and the rotationally driving forces given to the rollers 1 and 2 are controlled based on the detected result.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for manufacturing a solar cell, and more particularly to a method and an apparatus for manufacturing a solar cell in which a photovoltaic element and a sheet-like resin are integrally formed by passing between a pair of rollers. About.

[0002]

2. Description of the Related Art Conventionally, solar cells have been widely used as clean and non-depleting energy sources. Also,
Research and development of solar cells themselves are also being performed in a wide variety of ways, and solar cells that are well suited for installation on the ground and on roofs are being actively developed.

[0003] Such solar cells have begun to be used in a variety of shapes for a variety of applications, and various demands have been made in the production methods thereof.

[0004] For example, there is a technique described in JP-A-07-193266. The present technology is a method of manufacturing a solar cell in which a photovoltaic element and a sheet-shaped thermoplastic resin are integrally formed while being sandwiched and conveyed by a pair of rotating heating rollers. Solar cells themselves do not have sufficient resistance to outdoor environments such as temperature and humidity, and are often used by providing a coating material such as a resin on the front and back surfaces thereof. As a method of providing the coating material, a technique using a vacuum laminator device has been conventionally known. In this method, a photovoltaic element and a resin are put into a device closed with rubber, and the space is evacuated, whereby the photovoltaic element and the resin are thermocompression-bonded while being pressed at atmospheric pressure. On the other hand, the present technology described in Japanese Patent Application Laid-Open No. 07-193266 is one in which the size is not limited by the size of the solar cell to be manufactured because it is sandwiched and pressed by a heating roller, and is useful. .

[0005] Therefore, various techniques have been conventionally proposed because the technique of thermocompression bonding a solar cell using such a heating roller is useful.

[0006] Of course, such a technique is originally intended to heat and press a sheet-like material other than a solar cell such as a resin film,
Alternatively, there is a technology of pressure bonding using an adhesive material, and we studied to apply it to solar cells based on that technology,
It has been improved.

On the other hand, Japanese Patent Application Laid-Open No. H11-097727 discloses important information on the case where a tensile strain is applied to a photovoltaic element formed on a flexible substrate. That is, when a large tensile strain is applied to a photovoltaic element, the performance is affected. Characteristic value F. representing the performance of the photovoltaic element. F. Does not affect up to a certain amount of strain, but decreases when the strain value exceeds its critical value. Therefore, the F.
F. In this method, the photovoltaic element is subjected to tensile deformation processing with a strain amount equal to or less than the critical drop value.

[0008]

SUMMARY OF THE INVENTION Japanese Patent Application Laid-Open No. H11-0977
No. 27 does not consider that there is a possibility that the molding conditions may suddenly change in the manufacturing process. Even when the molding conditions are suddenly changed for some reason during manufacturing, there is no concept of devising the distortion amount to increase or detecting the fact that the distortion amount has increased.

Therefore, the technique described in Japanese Patent Application Laid-Open No. H11-097727 is only useful in a manufacturing method in which the initially set molding conditions do not change. if,
If you do not notice that the molding conditions can change suddenly, F. There is a possibility that a solar cell which is subjected to a tensile force that is equal to or higher than the reduced critical strain value and whose performance may be deteriorated may be continuously produced without knowing it.

[0010] In the technique as in the above example, a case in which the photovoltaic element receives a tensile force that causes a large strain value due to a sudden change in molding conditions will be briefly described below with reference to the drawings.

FIG. 10 shows a step of pressing an adhesive sheet material on the light receiving surface side of a photovoltaic element having a semiconductor photoactive layer formed on a flexible substrate. The roller pairs 1 and 2 apply pressure while holding the photovoltaic element 3 and the pressure-sensitive adhesive sheet material 4 while pressing with an independent rotation drive source to press the roller pair. The roller has a surface covered with rubber, and when a predetermined holding pressure is applied to the photovoltaic element 3 and the pressure-sensitive adhesive sheet material 4, the roller holds and conveys with a sufficient frictional force.

An adhesive made of a silicone resin is provided on the photovoltaic element side of the adhesive sheet member 4 and exerts sufficient adhesive force by applying a predetermined pressure for a predetermined time. In the present embodiment, two pairs of rollers are used to press the predetermined pressure by the pinching pressure of the roller pair and to press the roller for a predetermined time. With only one pair of rollers, in order to press only for a predetermined period of time, the rotation speed of the rollers becomes very slow, and the transport speed is slow, resulting in insufficient production efficiency. Therefore, in this example,
Two pairs of rollers are prepared.

In the process using the conventional technique as briefly described above, the rotation speed of the roller pair 1 is much lower than the rotation speed of the roller pair 2 and the roller pairs 1 and 2
It can be assumed that the photovoltaic element 3 is subjected to tensile strain between the holding portions 5 and 6 at (5) (represented by an arrow A).

The rotation speed of the roller pair 1 may be reduced because foreign matter is caught in the holding portion 5 or the tension shown by the arrow B is increased due to failure in feeding the adhesive sheet material. It can be considered as a sudden occurrence.

[0015] Therefore, the object of the present invention is to provide a case where molding conditions suddenly change in the manufacturing process.
An object of the present invention is to provide a coating material integrally with a photovoltaic element by utilizing the sandwiching pressure of a pair of rotating rollers without generating excessive distortion that degrades the performance of the photovoltaic element.

[0016]

SUMMARY OF THE INVENTION The above-mentioned technique relating to the technique of providing a coating material, that is, by passing a photovoltaic element and a sheet material between a pair of rotating rollers, makes use of the clamping pressure of the pair of rollers. Although many techniques for providing a coating material on a solar cell have been proposed, in these manufacturing methods, the photovoltaic element must not receive a tensile strain exceeding a certain value in consideration of sudden changes in molding conditions. There is no technology that proposes.

According to the present inventor, in the above-described conventional manufacturing method in which the coating material is integrally provided on the photovoltaic element by utilizing the sandwiching pressure of the rotating roller pair, the molding conditions suddenly change as described above. There is plenty of potential, so that the photovoltaic element F. The inventor has found that there is a sufficient possibility of receiving a tensile force that is equal to or higher than the reduced critical strain value, and as a result of intensive studies to address this, the present invention has the following structure.

That is, according to the first method for manufacturing a solar cell of the present invention, a photovoltaic element having at least one semiconductor photoactive layer on a flexible substrate and a sheet-like resin are rotatably driven by at least one roller. A step of preparing at least two pairs of rollers to which force is applied, and passing the photovoltaic element and the sheet-like resin between the at least two pairs of rollers, wherein the at least two pairs of rollers are used. In a method for manufacturing a solar cell integrally formed by applying a clamping pressure to the photovoltaic element and the sheet-shaped resin,
In a state where the photovoltaic elements are sandwiched between adjacent roller pairs, the photovoltaic elements are applied to the photovoltaic elements by the force generated by the difference in the conveying force at the sandwiching portion. F. A drive system having a safety mechanism set in advance to measure the drive conditions of the two pairs of rollers that generate a strain amount equal to or greater than the lowering critical value, and set so that the drive conditions measured in advance cannot be satisfied even instantaneously. Thus, the two pairs of rollers are driven.

The method for manufacturing a solar cell according to the first aspect of the present invention includes:
As a further preferable feature, "the optical semiconductor active layer is made of amorphous silicon", and in this case, "the safety mechanism operates such that the two pairs of the photovoltaic elements have a distortion amount of less than 0.7%. A mechanism for controlling the driving of the roller pair ".

In a second method of manufacturing a solar cell according to the present invention, a photovoltaic element having at least one semiconductor photoactive layer on a flexible substrate and a sheet-like resin are rotated by at least one roller. A step of preparing at least two pairs of rollers to which force is applied, and passing the photovoltaic element and the sheet-like resin between the at least two pairs of rollers, wherein the at least two pairs of rollers are used. In a method for manufacturing a solar cell integrally formed by applying a clamping pressure to the photovoltaic element and the sheet-shaped resin,
In a state in which the photovoltaic elements are sandwiched between the adjacent roller pairs, the amount of distortion of the photovoltaic elements is detected directly or indirectly by the force generated by the difference in the conveying force at the sandwiching portion, It is characterized in that a rotational driving force applied to the roller is controlled based on a detection result.

The method for manufacturing a solar cell according to the second aspect of the present invention comprises:
As a further preferable feature, "the control of the rotational driving force applied to the roller is performed such that the amount of distortion of the photovoltaic element does not exceed the FF lowering critical value of the photovoltaic element. ", The photovoltaic element is at or above the FF lowering critical value due to the force generated by the difference in the conveying force when one photovoltaic element is sandwiched between the two pairs of adjacent rollers. Having a step of directly or indirectly detecting the amount of distortion beforehand, "the optical semiconductor active layer is amorphous silicon", and in this case, "control of the rotational driving force applied to the roller is
The operation is performed so that the amount of distortion of the photovoltaic element is less than 0.7%. ”“ The amount of distortion of the photovoltaic element is measured by using a torque sensor attached to the roller that is providing a rotational driving force. Indirectly using the ``, the amount of distortion of the photovoltaic element, indirectly using a tachometer attached to the roller that is providing a rotational driving force, '' The amount of distortion of the photovoltaic element is indirectly detected by using a means for detecting a current flowing through an electric motor that is providing a rotational driving force to the roller. ''
"Indirectly detecting the amount of distortion of the photovoltaic element by using a means for detecting a vertical displacement of the photovoltaic element between a pair of rollers having at least a roller to which a rotational driving force is applied" ,including.

Further, the above-mentioned first and second methods of manufacturing the solar cell according to the present invention preferably have a further preferable feature that "the sheet-shaped resin is a thermoplastic resin, and at least one roller of the roller pair is a heating roller. And heat bonding the photovoltaic element and the thermoplastic resin ",
"The sheet-shaped resin has an adhesive on a surface side in contact with the photovoltaic element, and the photovoltaic element and the sheet-shaped resin are pressure-bonded", "The photovoltaic element is flexible. A semiconductor photoactive layer having a thickness smaller than the thickness of the flexible substrate on the flexible substrate. In the roller pair, the upper and lower roller surfaces have different deformation rates with respect to load. And, the roller having the smaller deformation rate is used because all the roller pairs are unified on the upper side or the lower side, and the side of the photovoltaic element provided with the semiconductor photoactive layer is the roller pair. And passing the roller between the pair of rollers such that the roller has the smaller deformation rate. "

Further, in the third solar cell manufacturing apparatus of the present invention, a photovoltaic element having at least one semiconductor photoactive layer on a flexible substrate and a sheet-like resin are rotatably driven by at least one roller. Prepare at least two pairs of rollers to which a force is applied, pass the photovoltaic element and the sheet-like resin between the at least two pairs of rollers,
In a solar cell manufacturing apparatus formed by applying a sandwiching pressure to the photovoltaic element and the sheet-shaped resin by the at least two pairs of rollers, the one photovoltaic element is disposed between adjacent roller pairs. In the state of being pinched, F.C. F. It is characterized by having a safety mechanism for preventing the drive conditions of the two pairs of rollers from generating a distortion amount equal to or greater than the lowering critical value from being satisfied.

According to the third solar cell manufacturing apparatus of the present invention,
As a further preferable feature, "the safety mechanism has a structure in which the rotation drive structure of the roller pair cannot output a rotation torque that generates a distortion amount equal to or greater than the FF lowering critical value." In a structure that cannot output a rotational torque that generates an amount of distortion equal to or greater than the FF lowering critical value, a constant torque clutch is provided on a rotary drive shaft of the roller pair. An elastic member provided between the shafts of the pair of rollers, and the elastic member shrinks without maintaining the distance between the shafts of the roller pair against a force that generates a strain amount equal to or greater than the FF lowering critical value. In this case, the elastic member is a coil spring, and shrinks with respect to a force that generates a strain amount equal to or more than the FF lowering critical value with respect to the photovoltaic element, The row The safety mechanism has a safety level adjustment mechanism that can change the driving condition that cannot be satisfied. ”The optical semiconductor active layer is amorphous. Silicon ", and in this case," the safety mechanism is a mechanism for controlling a rotational driving force applied to the roller so that the amount of distortion of the photovoltaic element is less than 0.7% ". .

Further, in the fourth solar cell manufacturing apparatus of the present invention, a photovoltaic element having at least one semiconductor photoactive layer on a flexible substrate and a sheet-like resin are rotatably driven by at least one roller. Prepare at least two pairs of rollers to which a force is applied, pass the photovoltaic element and the sheet-like resin between the at least two pairs of rollers,
In a solar cell manufacturing apparatus formed by applying a sandwiching pressure to the photovoltaic element and the sheet-shaped resin by the at least two pairs of rollers, the one photovoltaic element is disposed between adjacent roller pairs. In the sandwiched state, each unit has a means for directly or indirectly detecting the amount of distortion of the photovoltaic element by the force generated by the difference in the conveying force at the clamping unit, and the amount of distortion of the photovoltaic element is determined. It is characterized by having a means for processing and analyzing a signal from the detecting means and controlling a rotational driving force applied to the roller based on the result of the analysis.

According to the fourth solar cell manufacturing apparatus of the present invention,
As a further preferable feature, "the means for indirectly detecting the amount of distortion of the photovoltaic element has a torque sensor on a roller providing a rotational driving force",
"As a means for indirectly detecting an amount of distortion of the photovoltaic element, a tachometer is provided on a roller that applies a rotational driving force.", "Indirectly detecting an amount of distortion of the photovoltaic element." Means for detecting the current flowing through the electric motor that is applying a rotational driving force to the rollers, "and" as means for indirectly detecting the amount of distortion of the photovoltaic element, at least the rotational driving force Having means for detecting the vertical displacement of the photovoltaic element between a pair of rollers having a roller provided with the roller, "the optical semiconductor active layer is made of amorphous silicon", and in this case "the roller The means for controlling the rotational driving force applied to
Controlling the rotational driving force to be applied to the roller so that the amount of distortion of the photovoltaic element is less than 0.7% "," using a thermoplastic resin for the sheet-like resin, At least one roller is a heating roller, heat bonding the photovoltaic element and the thermoplastic resin "," the sheet-shaped resin has an adhesive material on the surface contacting the photovoltaic element Pressure bonding the photovoltaic element and the sheet-shaped resin ".

According to the present invention, in the manufacture of a solar cell using a pair of rotating rollers as described above, the photovoltaic element is added to the photovoltaic element. F. Without adding more strain than the critical value for lowering
The covering material can be integrally formed. It is characterized by taking into account the possibility that molding conditions may change due to some sudden factors during molding. F. It is possible to expect a very useful effect that it is possible to prevent continuous production without knowing the photovoltaic element to which a strain amount equal to or more than the lower critical value is applied.

[0028]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional view showing a state in which a coating material is integrally formed on a photovoltaic element according to an embodiment of the present invention, and FIG. 2 is a plan view of the state seen from above.

This example shows a step of pressing an adhesive sheet material on the light-receiving surface side of a photovoltaic element in which a semiconductor photoactive layer is formed on a flexible substrate, as in the above-described conventional technique. The photovoltaic element 3 of this example has a structure in which an amorphous silicon semiconductor layer is formed on a stainless steel substrate having a thickness of 0.15 mm. The roller pairs 1 and 2 have an electric pulse motor 7 as an independent rotary drive source. An electric pulse motor 7 is provided on the axis of the upper roller of each roller pair, and the upper roller and the lower roller of each roller pair are linked by a gear 8 on the side of each roller. The photovoltaic element 3 and the pressure-sensitive adhesive sheet material 4 are sent from the left side of the roller pair 1, are pressed by each roller pair, and are pressed. The pressure-sensitive adhesive sheet material 4 in this example is a transparent fluororesin sheet having a thickness of
It is provided with a transparent silicone resin-based adhesive material having a thickness of 0 μm. The roller has a surface covered with rubber, and when a predetermined holding pressure is applied to the photovoltaic element 3 and the pressure-sensitive adhesive sheet material 4, the roller holds and conveys with a sufficient frictional force.

By applying a predetermined pressure for a predetermined time to the silicone resin-based pressure-sensitive adhesive material of the pressure-sensitive adhesive sheet material 4,
It exhibits sufficient adhesive strength. In the present embodiment, two pairs of rollers are used to press the predetermined pressure by the pinching pressure of the roller pair and to press the roller for a predetermined time. With only one pair of rollers, in order to press only for a predetermined time, the rotation speed of the rollers becomes very slow,
As a result, the transfer speed is low, and sufficient production efficiency cannot be obtained. Therefore, in this example, two pairs of rollers are prepared.

The feature of this embodiment is that a constant torque clutch 9 is provided between the output shaft of the roller motor 2 from the pulse motor 7 and the shaft of the gear 8. The constant torque clutch 9 is a clutch that outputs and transmits up to a specified rotational torque value of the input rotational drive force, but does not transmit the rotational drive force by idling when the rotational torque value exceeds the specified rotational torque value. It is. For example, those having the following structure can be mentioned.

The constant torque clutch is normally composed of a pair of clutch members integrally connected by engagement with each other, and when the load torque becomes larger than the specified torque, one clutch member is connected to the other clutch member. By rotating while repeating the operation of riding on the projection of the clutch member, the rotational driving force is cut off. Therefore, by changing the height of the protrusion, the force of the spring pressing the mutual clutches, and the like, the specified torque that is a critical value can be changed.

For example, there is a dial capable of setting a specified torque on the surface of a constant torque clutch, and this dial is interlocked with a spring pressing the clutch.

In this embodiment, as described above, the rotational speed of the roller pair 1 can be reduced suddenly. For example, when there is a defective molded product in which only part of the adhesive material of the adhesive sheet 4 is applied very thickly, the rotation speed of the sandwiching portion 5 of the roller pair 1 may be reduced due to the following factors. There is. As the thickness of the adhesive sheet 4 increases, the rubber of the upper and lower rollers is compressed and greatly deformed. The pulse motor 7 tries to continue to apply the rotational driving force at a constant rotation speed, but this is equivalent to the fact that the outer diameter of the roller is reduced by the amount that the rubber is compressed and largely deformed, and the peripheral speed of the outer diameter of the roller is reduced.

In such a case, a difference occurs in the rotation speed between the roller pair 1 and the roller pair 2, and the holding portion 6 of the roller pair 2
Accordingly, the photovoltaic element 3 tries to be distorted by receiving a tensile force.

Therefore, the F.V. F. The driving conditions of the two pairs of rollers that generate the amount of distortion equal to or higher than the critical value for reduction are measured in advance.

In the present embodiment, first, at the start of daily production, a strain gauge capable of directly measuring the amount of distortion of the photovoltaic element is attached to the photovoltaic element and passed through a manufacturing apparatus. At this time,
The rotation speed of the roller pair 2 is set to be higher than the rotation speed of the roller pair 1 for each of the pulse motors serving as the driving sources. This speed difference is slightly increased to F. The driving conditions of the two pairs of rollers that generate a distortion amount equal to or greater than the critical value for reduction are determined.

In this embodiment, the photovoltaic element 3 is formed by forming an amorphous silicon semiconductor layer on a stainless steel substrate having a thickness of 0.15 mm as described above. F. It has been confirmed by an experiment that the lower critical strain is 0.7%. This F. F. The lower critical value distortion amount will be described later.

Thus, by the above method, the speed difference between the two roller pairs at which the distortion amount of the photovoltaic element becomes 0.65% is determined. This 0.65% is the critical strain amount of 0.1 as described above.
This is a margin for 7%. At the same time, the rotational torque applied to the drive source of the roller pair 2 at that time is measured.

Next, the rotational torque value is set as a specified torque value of the constant torque clutch by adjusting the adjusting means of the constant torque clutch.

In this manner, the constant torque clutch 9 does not transmit a rotational torque exceeding the specified value to the roller pair 2. F. It is possible to prevent the application of a tensile force that generates a strain amount equal to or more than the lowering critical value.

Here, the pulse motor 7 of the roller pair 2
Has a sufficiently large rotating torque and tries to keep rotating at a constant speed. Therefore, even if the roller pair 2 tries to receive the rotation torque in the anti-rotation direction due to the rotation speed of the roller pair 1 becoming slow, the roller pair 2 tries to overcome the rotation torque and try to rotate. However, the constant torque clutch 9 provided between the pulse motor and the roller pair idles due to the excessive rotation torque.

As a result, at the moment when the rotation speed of the roller pair 1 suddenly decreases, the excessive rotation torque of the pulse motor of the roller pair 2 is not transmitted to the rollers, and the excessive pulling force is applied to the photovoltaic element 3. Can be prevented from being added.

By performing as described above, slight differences in daily manufacturing conditions, that is, changes in material conditions such as changes in the thickness of the sheet-shaped resin, and deterioration in the rubber of the roller change its hardness. Incorporating various change factors such as affecting the rotation speed, the F.V. F. It is possible to realize a manufacturing method that does not generate a strain amount equal to or more than the critical value for lowering.

Another advantage of this embodiment is that the relationship between the amount of distortion of the photovoltaic element and the rotational torque can be determined in the actual configuration at the time of manufacture.

A feature of the method for manufacturing a solar cell using a roller pair is that the solar cell is manufactured using a flexible member. Using resin as a coating material for photovoltaic elements,
To avoid damaging the solar cells, rubber is used for the rollers. By interposing such a flexible member, there is a possibility that dimensional stability may be deteriorated as compared with, for example, processing an iron plate with an iron roller. Therefore, it is very useful to be able to easily measure the relationship between the amount of distortion of the photovoltaic element and the rotational torque in the actual configuration at the time of manufacture as in this example.

F. in the present invention. F. The lower critical value distortion amount is defined as described in Japanese Patent Application Laid-Open No. H11-097727.
The following is the same as the content described in the official gazette.

First, as the amount of distortion, the maximum amount of distortion generated by receiving a tensile force is taken into consideration. It can be instantaneous or persistent. This distortion amount will be referred to as a peak distortion amount.
It is difficult to discuss the power generation performance of the photovoltaic element based on the amount of strain remaining after releasing the tensile force.

Next, referring to FIG. F. The definition of the lower critical value will be described.

The amount of distortion of the photovoltaic element and F.F. F. Graph the relationship between the rates of change. In that case, as shown in FIG.
In terms of a certain amount of distortion, F.I. A decrease in F occurs. This F.
F. Is a gentle curve, a tangent is drawn as shown in the figure, and it is an intersection of two tangents.
F. The amount of strain at which the rate of decrease is about 1% of the initial F. The lower critical value is used. In the case of FIG. 3 using amorphous silicon, the intersection of the two tangents is 7000 με (0.7%
Distortion). That is, when the peak strain exceeds 7000 με, F.R. F. Decrease.

Here, F.S. F. Will be described.

F. F. = Maximum power (Pm) / (short circuit current (Isc) × open circuit voltage (Voc)). That is, as a physical meaning, the power Pm that can be actually extracted is compared with the product of Voc, which is the value when only the voltage is extracted to the maximum, and Isc, the value when the current is extracted to the maximum. Value.
Practical F. F. Is determined by the forward characteristics of the pn junction. Therefore, if a leakage current flows through a defect included in the semiconductor substrate to be used or a defect generated at the time of manufacturing the pn junction or in a subsequent manufacturing process, F.F. F. And the output that should be able to be output is reduced. In this sense, F.F. F. That is, the fact that the semiconductor layer has a defect due to the tensile test.

As can be seen from the above, in the case of amorphous silicon, when the peak strain is 0.7% or more, that is, F. F. When a strain equal to or more than the lowering critical value is applied to the photovoltaic element, it is considered that the photovoltaic element has a defect.

Next, each element used in the present invention will be described.

[Solar Cell] The solar cell in the present invention is a solar cell having a photovoltaic element described later having at least a coating material. There is no particular limitation on whether the coating material is used for the light receiving surface or the non-light receiving surface or for both.

[Photovoltaic Element] The photovoltaic element used in the solar cell according to the present invention is not particularly limited, except that it has at least one semiconductor photoactive layer on a flexible substrate. Examples of photovoltaic devices include, for example, crystalline silicon photovoltaic devices, polycrystalline silicon photovoltaic devices, amorphous silicon photovoltaic devices, copper indium selenide photovoltaic devices, compound semiconductor photovoltaic devices, and the like. Can be used.

However, considering that it is formed on a flexible substrate, it is preferable to use amorphous silicon having sufficient flexibility for the photoactive layer.

The flexible substrate is not particularly limited, and examples thereof include a resin sheet material and a thin metal plate. However, a stainless steel substrate is preferable in consideration of structural strength, corrosion resistance, and the like.

[Sheet-shaped resin] The sheet-shaped resin is used as a coating material for the solar cell of the present invention, and may be any resin that can be adhered and adhered to the photovoltaic element by the above-mentioned steps. It does not do.

However, for example, when it is provided on the light receiving surface side,
It preferably has the following properties. First, it is preferable to have translucency. This is because, in the case where a material serving as an adhesive or an adhesive is provided on the resin serving as the base as well as the resin serving as the sheet-like base, it is preferable that the material also has translucency.

Further, it is preferable to have weather resistance. Even when exposed to an outdoor environment for a long time, by maintaining sufficient translucency, the power generation performance of the photovoltaic element is not affected. Also in this weather resistance, it is preferable that the material is provided in a material serving as an adhesive or an adhesive.

Further, it is preferable that the resin, the adhesive, and the adhesive as the sheet-shaped substrate have waterproofness, moistureproofness, insulation, scratch resistance, and flexibility.

On the other hand, for example, when it is provided on the non-light receiving surface side,
Of the above properties, translucency is not necessarily required,
It is preferable to have the above properties.

In the case of thermocompression bonding to a photovoltaic element using a heating roller, the resin serving as the adhesive is preferably thermoplastic.

[Roller Pair] The roller pair of the present invention is characterized in that at least one roller is provided with at least two roller pairs to which a rotational driving force is applied.

Further, it is highly preferable that the material sandwiched between the roller surface, that is, the photovoltaic element and the sheet-like resin, does not slip at the sandwiched and contacting portion. If slipping occurs, the photovoltaic element will behave differently even if the rotation of the roller rotates at the desired speed and rotational driving force. Will not be alive.

Therefore, rubber and the like can be mentioned as preferable materials for the roller surface.

[Safety Mechanism] In the present invention, the driving condition of the two roller pairs is F.R. F. The safety mechanism for preventing the driving condition for generating the strain amount equal to or larger than the critical value for lowering from being instantaneously satisfied is as follows.

In the present invention, a manufacturing apparatus having at least two pairs of rollers to which a rotational driving force is applied as described above is used. F. F. The purpose is to prevent the application of a tensile force that generates a strain amount equal to or greater than the critical value for lowering. Even if a force up to the performance limit that can be pulled by this device is exerted, the photovoltaic element has its F.P.
F. This means that it is impossible to generate a strain amount equal to or more than the critical value for lowering.

The photovoltaic element was replaced by its F.I. F. The following conditions are necessary for pulling to generate a strain amount equal to or larger than the critical value for lowering. First, the shafts of adjacent roller pairs must be firmly supported and fixed. The drive roller must be given sufficient rotational torque. These are these two.

Therefore, the above-mentioned special mechanism is a mechanism for eliminating at least one of these two conditions.

The mechanism is as follows. One is that the pair of driving rollers on the upstream side for nipping and transporting the photovoltaic element are arranged.
This limits the rotational torque that can be generated by the downstream drive roller pair. As described above, F.A. F. The tensile force that generates a strain amount equal to or greater than the critical value for drop is determined by the photovoltaic element used. Then, the rotational torque for generating the pulling force is also determined. Therefore, the rotation torque is limited so as not to be generated. The means for restricting the rotation torque from being generated will be described below.

Second, the shaft of the downstream drive roller pair moves toward the upstream roller pair when the photovoltaic element is to be pulled with an excessive force. As a result, although the photovoltaic element has a sufficient force for pulling, the photovoltaic element cannot be pulled as a result of the reduction in the distance of the sandwiched portion.

Next, the above-mentioned means for restricting the rotation torque from being generated is a mechanism for preventing a sufficient rotation torque from being transmitted to the rollers. Therefore, the limit of the capability of the motor which is the rotary drive source is limited to the above-mentioned F. F. It may not be possible to generate a strain amount equal to or more than the critical drop value, or, as described above, a constant torque clutch that does not transmit a force equal to or more than a specified rotational torque is provided in the middle of the drive transmission means. Is also good.

Further, in the present invention, the driving conditions that make it impossible to satisfy even instantaneously (that is, the driving conditions of the two pairs of rollers necessary to generate the amount of distortion equal to or more than the FF lowering critical value). Is a mechanism having a means for adjusting the safety level.

This safety level adjusting mechanism is a means for adjusting the specified torque when a constant torque clutch is used as the safety mechanism as described later, and when the coil spring is used as the safety mechanism, the safety spring is pressed. Means for adjusting the position at which the ends of the coil springs are fixed to adjust the force can include, but are not limited to.

[Constant Torque Clutch] In the present invention, the use of a constant torque clutch is not limited to the constant torque clutch having the above-described structure. Any structure that does not transmit a rotational driving force greater than the specified rotational torque may be used. The constant torque clutch itself has been studied in the past, there are various types, and a great many are useful.

[Detection Means] In the present invention, the amount of distortion of the photovoltaic element may be detected by directly detecting the transport speed of the photovoltaic element, The rotation speed and the rotation driving force of the pair of rotations may be detected.

For example, it is conceivable to detect a current flowing through an electric motor that rotates a pair of rollers at a constant rotation speed.

By detecting the current flowing through the electric motor, the rotational torque of the electric motor is reduced by the above F.R. F. This current can be suppressed so as not to flow any more when it is attempted to reach a rotational torque that generates a distortion amount equal to or greater than the critical value for lowering. By controlling the current flowing through the electric motor, the rotation speed of the electric motor is reduced, and F. It is possible to suppress the rotation torque to a value that generates a distortion amount equal to or more than the critical value for reduction.

[0082]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method and an apparatus for manufacturing a solar cell according to the present invention will be described based on examples. Note that the present invention is not limited to these examples.

(Embodiment 1) This embodiment is characterized in that a coil spring 10 is provided between the shafts of the roller pair 1 and the roller pair 2. Other points that are not specified are the same as those of the above-described embodiment of the present invention.

A brief description will be given below with reference to FIGS. FIG. 4 is a plan view of this embodiment viewed from above, and FIG.
FIG. 4 is a partially enlarged cross-sectional view illustrating a relationship between a bearing portion of a roller pair 2 and an apparatus main body panel. The coil spring 10 is provided between the shafts of the roller pair 1 and the roller pair 2 to ensure the position of the roller pair 2 with respect to the roller pair 1 in a normal operation state. At this time, the roller pair 1 is fixed to the manufacturing apparatus main body of this embodiment, and its position does not move. On the other hand, the position of the roller pair 2 with respect to the roller pair 1 is determined by the coil spring 10. In FIG. 4, an apparatus main body panel 12 includes a shaft 1 of a roller pair 2.
4. An elongated hole 11 for supporting the bearing 13 is provided.
The shaft 14 and the bearing 13 are elongated by the coil spring 10.
Is a normal position in a normal operation state.

In the above configuration, when the rotation speed of the roller pair 1 suddenly decreases as described above,
The roller pair 2 generates a rotational torque in the anti-rotational direction.
At this time, if the axis of the roller pair 2 is not fixed, the axis of the roller pair 2 moves to reduce the distance between the axis of the roller pair 1 and the axis. If the force to be moved is larger than the spring force of the coil spring 10, the shaft of the roller pair 2 moves, thereby reducing the distance between the roller pair 1 and the shaft. In that case, no excessive tensile force is applied to the photovoltaic element 3.

However, this is a technique for suddenly decreasing the rotation speed of the roller pair 1 for an extremely short time, and cannot be applied when the rotation speed continues to decrease. Therefore, when the position of the roller pair 2 reaches a predetermined position by the coil spring 10, it is detected by a position sensor (not shown) and the entire apparatus is stopped. Then, the operation is restarted after the adjustment. This can prevent an excessive amount of tensile strain from being applied to the photovoltaic element.

In this embodiment, the proper pressing force of the coil spring 10 is exerted as follows.

Using a load cell in the portion where the coil spring 10 is provided in FIG.
%, The load for supporting the space between the shafts is measured. Next, the other end of the coil spring is fixed at a position where the roller pair 2 can be pressed with the above-mentioned measured load based on basic data indicating the amount of contraction of the coil spring and the load at that time.

Therefore, the present embodiment is directed to the F.V.
F. It is possible to realize a manufacturing method that does not generate a strain amount equal to or more than the critical value for lowering.

(Embodiment 2) This embodiment is characterized in that a torque sensor 15 is provided between the pulse motor 7 and the gear 8 of the roller pair 2. Other points that are not specified are the same as those of the above-described embodiment of the present invention.

In this embodiment, as shown in FIG. 6, the rotational torque value of the roller pair 2 is always grasped by the torque sensor 15.

Therefore, as described above, when the rotation speed of the roller pair 1 suddenly decreases and a rotation torque is generated in the roller pair 2 in the anti-rotation direction, the rotation torque value read by the torque sensor becomes excessively large. Become. There is a control unit (not shown) for processing and analyzing this signal, and a signal is sent from this control unit instantaneously to reduce the rotation speed of the pulse motor 7. Thus, the rotational torque of the roller pair 2 is controlled, and the photovoltaic element is supplied with F.R. F. This is to prevent the application of an excessive tensile force that generates a strain amount equal to or more than the critical value for lowering.

(Embodiment 3) This embodiment is characterized in that a tachometer 16 is provided between the pulse motor 7 and the gear 8 of the roller pair 1 and the roller pair 2 respectively. Other points that are not specified are the same as those of the above-described embodiment of the present invention.

In this embodiment, as shown in FIG. 7, the rotation speed of the roller pair 1 and the roller pair 2 is detected by the tachometer 16 and the speed difference is always grasped.

Therefore, when the rotational speed of the roller pair 1 suddenly decreases as described above, the speed difference becomes excessive. There is a control unit (not shown) for processing and analyzing this signal, and a signal is sent from this control unit instantaneously to reduce the rotation speed of the pulse motor 7 of the roller pair 2. This controls the rotational speed difference between the roller pair 1 and the roller pair 2 and causes the photovoltaic element to have an F.R. F. This is to prevent the application of an excessive tensile force that generates a strain amount equal to or more than the critical value for lowering.

(Embodiment 4) This embodiment is characterized in that a proximity sensor 17 is provided at an intermediate point between the roller pair 1 and the roller pair 2. Other points that are not specified are the same as those of the above-described embodiment of the present invention.

In the present embodiment, a proximity sensor 17 is provided above the photovoltaic element 3 at an intermediate point between the roller pair 1 and the roller pair 2 as shown in FIG. This proximity sensor 17
, The distance from the photovoltaic element 3 is always known. Since the photovoltaic element 3 of this embodiment has flexibility, if it is slightly bent between the pair of rollers as shown in FIG. 8 when it is first started up, unless a tensile force is applied. Similarly, it remains deflected. However, if the rotation speed of the roller pair 1 suddenly decreases as described above, a tensile force starts to be applied, the bending becomes small, and the photovoltaic element approaches the proximity sensor 17.

The proximity sensor 1 is provided in the apparatus of this embodiment.
There is a control unit (not shown) for processing and analyzing the signal from the control unit 7. The control unit transmits the signal instantaneously to reduce the rotation speed of the pulse motor 7 of the roller pair 2. As a result, the photovoltaic element between the roller pair 1 and the roller pair 2 is not subjected to a pulling force, and is maintained in a state in which the photovoltaic element is naturally slightly bent as when starting to start for the first time.

(Embodiment 5) This embodiment is characterized in that a heating roller is used as a roller pair and a thermoplastic resin is heated and pressed. Other points that are not specified are the same as those of the above-described embodiment of the present invention.

In this embodiment, as shown in FIG. 9, the sheet-like resin 2 is provided on both the light receiving surface side and the non-light receiving surface side of the photovoltaic element 3.
0 and 21 are integrally formed. The sheet-like resin 20 provided on the light receiving surface side of the photovoltaic element 3 has a thickness of 50 μm.
An EVA resin (ethylene-vinyl acetate copolymer), which is a thermoplastic resin, is integrally laminated with a thickness of 100 μm on the fluororesin sheet of (1). Similarly, a sheet-shaped resin 21 provided on the non-light-receiving surface side of the photovoltaic element 3 is a PET sheet having a thickness of 50 μm, and EVA (ethylene-vinyl acetate copolymer) which is also a thermoplastic resin as an adhesive material. It has a thickness of 100 μm and is integrally laminated.

Further, the roller pair 18 and the roller pair 19
Is a roller similar to that of the above embodiment of the invention, but a heating roller having a controllable heating heater.

Embodiment 6 In this embodiment, the rubber hardness of the roller used on the upper side is harder than the rubber hardness of the roller used on the lower side. It is characterized in that it passes through the device so that it is on the upper roller side having a high hardness. Other points that are not specified are the same as those of the embodiment.

In this example, the rubber hardness of the upper roller 22 is 45 °, and the rubber hardness of the lower roller 23 is 35 °.
°, and a photovoltaic element is used in which a semiconductor photoactive layer having a thickness of about 1 μm is provided on a stainless steel substrate having a thickness of 150 μm.

This example demonstrates the effect in the following cases.

FIG. 11 shows the lumps 2 where the pressure-sensitive adhesive material of the pressure-sensitive adhesive sheet material 4 was not uniformly applied and was solidified in this example.
4 shows how the roller 4 is held between the roller pair 1. In such a case, the thickness suddenly increases from the normal thickness by the thickness of the dam portion 24. It is necessary to absorb this increase somewhere, but in this example, the lower roller having a rubber hardness of 35 ° is deformed and absorbs. Therefore, the photovoltaic element 3 is bent so as to project downward at the holding portion of the roller pair 1 as shown in FIG. And roller pair 1 and roller pair 2
Between the roller pair 2, the roller pair 2 is bent so as to be convex downward. Note that the photovoltaic element between the roller pair 1 and the roller pair 2 is described in F.F. F. It does not receive a tensile strain higher than the lower critical value.

Here, the fact that the photovoltaic element is distorted by being bent will be described. When the photovoltaic element is bent, the center in the thickness direction of the photovoltaic element becomes a neutral plane of bending. The neutral surface is a surface that is not subjected to compression and tensile strains due to bending. A convex side, that is, an outer side, receives tensile strain from the neutral surface, and a concave side, that is, an inner side, receives compressive strain from the neutral surface. And, the farther from the neutral surface, the greater the amount of compression and tensile strain.

In the present example, the semiconductor photoactive layer is subjected to compressive strain at the above-described holding portion between the roller pairs. That is, since the photovoltaic element of this example has a semiconductor photoactive layer with a thickness of about 1 μm provided on a stainless steel substrate with a thickness of 150 μm, the neutral surface of the bending is substantially at the center of the stainless substrate with a thickness of 150 μm. And the semiconductor photoactive layer on the surface thereof is surely subjected to compressive strain.

F. F. Is a strain due to tension, and a strain due to compression causes a defect in the semiconductor photoactive layer to cause a defect. F. Is not reduced, and there is no concern about bending at the holding portion by the roller pair.

Here, the portion between the roller pair 1 and the roller pair 2 is slightly convexly bent upward, and the semiconductor photoactive layer is subjected to tensile strain. However, since the bending curvature is large, only a very small tensile strain is generated.
In bending, the larger the curvature, the smaller the amount of distortion,
The smaller the curvature, the larger the distortion amount. Therefore, there is a concern about bending at the holding portion, which has a much smaller curvature than bending between the roller pair 1 and the roller pair 2.

However, in this example, as described above, since the lower roller than the upper roller is a roller using a material having a high deformation rate, the photovoltaic element is held at the holding portion of this roller pair. Turns convex to the side. Thereby, F.I. F. There is no need to worry about the occurrence of tensile strain that causes a decrease.

[0111]

As described above, according to the present invention,
It is possible to provide a manufacturing method and a manufacturing apparatus in which a coating material is provided on a photovoltaic element without giving a tensile strain that affects the power generation performance thereof. Here, a characteristic effect of the present invention is that no excessive tensile strain is applied to the photovoltaic element even when the molding conditions are suddenly changed.

As a result, it is possible to prevent the photovoltaic element from continuing to produce a solar cell in which an excessive tensile strain is unknowingly imposed and the power generation performance may be deteriorated.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a method for manufacturing a solar cell according to the present invention.

FIG. 2 is a plan view showing an embodiment of a method for manufacturing a solar cell according to the present invention.

FIG. 3 is a graph showing a relationship between a peak distortion amount of a photovoltaic element and F.F. F. FIG.

FIG. 4 shows a first embodiment of a method of manufacturing a solar cell according to the present invention.
FIG.

FIG. 5 is a first embodiment of a method of manufacturing a solar cell according to the present invention.
FIG.

FIG. 6 is a second embodiment of a method for manufacturing a solar cell according to the present invention.
FIG.

FIG. 7 shows a third embodiment of a method for manufacturing a solar cell according to the present invention.
FIG.

FIG. 8 is a fourth embodiment of the method of manufacturing a solar cell according to the present invention.
FIG.

FIG. 9 is a fifth embodiment of the method of manufacturing a solar cell according to the present invention.
FIG.

FIG. 10 is a cross-sectional view illustrating a conventional method for manufacturing a solar cell.

FIG. 11 is a sectional view showing Example 6 of the method for manufacturing a solar cell according to the present invention.

[Explanation of symbols]

 1, 2 Roller pair 3 Photovoltaic element 4 Adhesive sheet material 5, 6 Holder 7 Pulse motor 8 Gear 9 Constant torque clutch 10 Coil spring 11 Slot 12 Device body panel 13 Bearing 14 Shaft 15 Torque sensor 16 Tachometer 17 Proximity Sensor 18, 19 Heating roller pair 20 Fluororesin sheet having EVA resin 21 PET sheet having EVA resin

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 5F051 AA05 BA14 BA18 GA02 GA05 JA05

Claims (32)

[Claims] 1. A photovoltaic device having at least one semiconductor photoactive layer on a flexible substrate and a sheet-like resin, and at least one roller has at least two pairs of rollers to which a rotational driving force is applied. Providing a step of passing the photovoltaic element and the sheet-like resin between the at least two pairs of rollers, and passing the photovoltaic element and the sheet-like resin by the at least two pairs of rollers. In a method of manufacturing a solar cell integrally formed by applying a clamping pressure, in a state where the one photovoltaic element is clamped between adjacent roller pairs, a force generated by a difference in a conveying force at the clamping portion is used. And F.F. F. A drive system including a safety mechanism set in advance to measure the drive conditions of the two pairs of rollers that generate a strain amount equal to or greater than the critical drop value, and to set the drive conditions so that the measured drive conditions cannot be satisfied even instantaneously. A method for manufacturing the solar cell, wherein the two pairs of rollers are driven. 2. The method according to claim 1, wherein the optical semiconductor active layer is made of amorphous silicon. 3. The safety mechanism according to claim 2, wherein the driving mechanism controls the driving of the two pairs of rollers so that the amount of distortion of the photovoltaic element is less than 0.7%.
3. The method for manufacturing a solar cell according to 1. 4. A photovoltaic element having at least one semiconductor photoactive layer on a flexible substrate and a sheet-shaped resin, and at least one roller has at least two pairs of rollers to which a rotational driving force is applied. Providing a step of passing the photovoltaic element and the sheet-like resin between the at least two pairs of rollers, and passing the photovoltaic element and the sheet-like resin by the at least two pairs of rollers. In a method for manufacturing a solar cell integrally formed by applying a clamping pressure, in a state where the one photovoltaic element is clamped between adjacent roller pairs, a force generated by a difference in a conveying force at the clamping portion is used. A method for manufacturing a solar cell, comprising: directly or indirectly detecting an amount of distortion of a photovoltaic element, and controlling a rotational driving force applied to a roller based on the detection result. 5. The control of the rotational driving force applied to the roller is such that the amount of distortion of the photovoltaic element is equal to the F.F. F. The method for manufacturing a solar cell according to claim 4, wherein the distortion is performed so as not to have a strain amount equal to or more than a critical value for lowering. 6. A force generated by a difference in conveying force in a state where one photovoltaic element is sandwiched between the two pairs of adjacent rollers, and the photovoltaic element is driven by an F.C. F. The method for manufacturing a solar cell according to claim 4, further comprising a step of directly or indirectly detecting in advance a strain amount that is equal to or greater than a critical drop value. 7. The method according to claim 4, wherein the optical semiconductor active layer is made of amorphous silicon. 8. The solar cell according to claim 7, wherein the control of the rotational driving force applied to the roller is performed such that the amount of distortion of the photovoltaic element is less than 0.7%. Production method. 9. The method according to claim 4, wherein the amount of distortion of the photovoltaic element is indirectly detected by using a torque sensor attached to the roller that applies a rotational driving force. A method for manufacturing a solar cell as described in 10. The method according to claim 4, wherein the amount of distortion of the photovoltaic element is indirectly detected by using a tachometer attached to the roller that applies a rotational driving force. A method for manufacturing a solar cell according to any one of the above. 11. The apparatus according to claim 4, wherein the amount of distortion of the photovoltaic element is indirectly detected by using a means for detecting a current flowing through an electric motor that applies a rotational driving force to the roller. 9. The method for manufacturing a solar cell according to any one of claims 1 to 8. 12. The amount of distortion of the photovoltaic element is indirectly measured by means of detecting a vertical displacement of the photovoltaic element between at least a pair of rollers having a roller to which a rotational driving force is applied. 5. The method according to claim 4, wherein the detection is performed.
9. The method for manufacturing a solar cell according to any one of claims 1 to 8. 13. The sheet-like resin is made of a thermoplastic resin, and at least one roller of the roller pair is a heating roller, and the photovoltaic element and the thermoplastic resin are heat-bonded. A method for manufacturing a solar cell according to claim 1. 14. The sheet-shaped resin has an adhesive material on a surface contacting the photovoltaic element, and the photovoltaic element and the sheet-shaped resin are pressure-bonded. 13. The method for manufacturing a solar cell according to any one of 12 above. 15. The photovoltaic device, wherein a semiconductor photoactive layer having a thickness smaller than the thickness of the flexible substrate is provided on a flexible substrate. In the roller pair, upper and lower rollers are provided. The material of the surface uses a material having a different deformation rate with respect to the load, and using the roller having the smaller deformation rate is unified on the upper or lower side for all the roller pairs, and the photovoltaic element The side provided with the semiconductor photoactive layer,
The method of manufacturing a solar cell according to claim 1, wherein the roller pair is passed between the pair of rollers such that the pair of rollers has a smaller deformation rate. 16. A photovoltaic device having at least one semiconductor photoactive layer on a flexible substrate, and a sheet-like resin.
At least one roller is provided with at least two pairs of rollers to which a rotational driving force is applied, and the photovoltaic element and the sheet-like resin are passed between the at least two pairs of rollers. A photovoltaic element and a sheet-like resin are integrally formed by applying a nip pressure to the photovoltaic element and the sheet-like resin, wherein the one photovoltaic element is sandwiched between adjacent roller pairs, respectively. In this state, the photovoltaic element is subjected to F.F. F. An apparatus for manufacturing a solar cell, comprising: a safety mechanism for preventing a drive condition of the two pairs of rollers from generating a distortion amount equal to or more than a critical drop value. 17. The safety mechanism according to claim 16, wherein a rotational drive structure of the roller pair is the same as the F.R. F. 17. The apparatus for manufacturing a solar cell according to claim 16, wherein the solar cell manufacturing apparatus has a structure that cannot output a rotational torque that generates a strain amount equal to or more than a critical value for reduction. 18. The method according to claim 18, wherein F. 18. The solar cell manufacturing apparatus according to claim 17, wherein in the structure that cannot output a rotational torque that generates a distortion amount equal to or more than a critical value for reduction, a constant torque clutch is provided on a rotary drive shaft of the roller pair. 19. The safety mechanism has an elastic member between the shafts of the pair of rollers having the rotational driving force. F. 17. The apparatus for manufacturing a solar cell according to claim 16, wherein the apparatus has a structure in which the distance between the shafts of the roller pair cannot be maintained and contracts with respect to a force that generates a strain amount equal to or more than a critical value for reduction. . 20. The elastic member according to claim 1, wherein the elastic member is a coil spring. F. 20. The solar cell manufacturing apparatus according to claim 19, wherein the distance between the shafts of the pair of rollers is reduced by contracting with respect to a force that generates a strain amount equal to or more than a critical value for reduction. 21. The safety mechanism according to claim 16, wherein the safety mechanism has a safety level adjusting mechanism capable of changing the driving condition that cannot be satisfied.
The solar cell manufacturing apparatus according to any one of the above. 22. The solar cell manufacturing apparatus according to claim 16, wherein said optical semiconductor active layer is made of amorphous silicon. 23. The safety mechanism according to claim 22, wherein the safety mechanism is a mechanism for controlling a rotational driving force applied to the roller such that a distortion amount of the photovoltaic element is less than 0.7%. An apparatus for manufacturing the solar cell according to the above. 24. A photovoltaic device having at least one semiconductor photoactive layer on a flexible substrate, and a sheet-like resin,
At least one roller is provided with at least two pairs of rollers to which a rotational driving force is applied, and the photovoltaic element and the sheet-like resin are passed between the at least two pairs of rollers. A photovoltaic element and a sheet-like resin are integrally formed by applying a pinching pressure to the photovoltaic element and the sheet-shaped resin by the roller pair. In this state, the device has means for directly or indirectly detecting the amount of distortion of the photovoltaic element due to the force generated by the difference in the conveying force at the holding portion. And means for controlling the rotational driving force applied to the roller based on the analysis result. 25. A roller according to claim 2, wherein said photovoltaic element has a torque sensor as a means for indirectly detecting an amount of distortion of said photovoltaic element.
5. The apparatus for manufacturing a solar cell according to 4. 26. The solar cell according to claim 24, wherein as a means for indirectly detecting an amount of distortion of the photovoltaic element, a tachometer is provided on a roller that applies a rotational driving force. Manufacturing equipment. 27. The apparatus according to claim 27, wherein the means for indirectly detecting the amount of distortion of the photovoltaic element includes means for detecting a current flowing through an electric motor that applies a rotational driving force to the roller. 25. The apparatus for manufacturing a solar cell according to 24. 28. As means for indirectly detecting the amount of distortion of the photovoltaic element, a vertical displacement of the photovoltaic element between a pair of rollers having at least a roller to which a rotational driving force is applied is detected. 25. The apparatus for manufacturing a solar cell according to claim 24, further comprising means. 29. The solar cell manufacturing apparatus according to claim 24, wherein said optical semiconductor active layer is made of amorphous silicon. 30. The means for controlling the rotational driving force applied to the roller controls the rotational driving force applied to the roller such that the amount of distortion of the photovoltaic element is less than 0.7%. The apparatus for manufacturing a solar cell according to claim 29, wherein: 31. The sheet-like resin is made of a thermoplastic resin, and at least one roller of the pair of rollers is a heating roller, and the photovoltaic element and the thermoplastic resin are heated and bonded. An apparatus for manufacturing a solar cell according to claim 16. 32. The sheet-like resin has an adhesive material on a surface in contact with the photovoltaic element, and the photovoltaic element and the sheet-like resin are pressure-bonded. 30. The solar cell manufacturing apparatus according to any one of 30.